[Frontend] SE-0463: Enable SendableCompletionHandlers feature by default

include/swift/Basic/Features.def

@@ -253,6 +253,7 @@ LANGUAGE_FEATURE(BuiltinEmplaceTypedThrows, 0, "Builtin.emplace typed throws")
 SUPPRESSIBLE_LANGUAGE_FEATURE(MemorySafetyAttributes, 458, "@unsafe attribute")
 LANGUAGE_FEATURE(ValueGenerics, 452, "Value generics feature (integer generics)")
 LANGUAGE_FEATURE(RawIdentifiers, 451, "Raw identifiers")
+LANGUAGE_FEATURE(SendableCompletionHandlers, 463, "Objective-C completion handler parameters are imported as @Sendable")
 
 // Swift 6
 UPCOMING_FEATURE(ConciseMagicFile, 274, 6)
@@ -343,10 +344,6 @@ EXPERIMENTAL_FEATURE(ForwardModeDifferentiation, false)
 /// conformances.
 EXPERIMENTAL_FEATURE(AdditiveArithmeticDerivedConformances, false)
 
-/// Whether Objective-C completion handler parameters are imported as
-/// @Sendable.
-EXPERIMENTAL_FEATURE(SendableCompletionHandlers, false)
-
 /// Enables opaque type erasure without also enabling implict dynamic
 EXPERIMENTAL_FEATURE(OpaqueTypeErasure, true)
 

lib/Sema/TypeCheckDeclObjC.cpp

@@ -3889,12 +3889,27 @@ class ObjCImplementationChecker {
       diagnoseVTableUse(cand);
       return;
 
-    case MatchOutcome::WrongSendability:
+    case MatchOutcome::WrongSendability: {
+      auto concurrencyLevel = req->getASTContext().LangOpts.StrictConcurrencyLevel;
+
+      DiagnosticBehavior behavior;
+      switch (concurrencyLevel) {
+      case StrictConcurrency::Complete:
+        behavior = DiagnosticBehavior::Warning;
+        break;
+
+      case StrictConcurrency::Targeted:
+      case StrictConcurrency::Minimal:
+        behavior = DiagnosticBehavior::Ignore;
+        break;
+      }
+
       diagnose(cand, diag::objc_implementation_sendability_mismatch, cand,
                getMemberType(cand), getMemberType(req))
-          .limitBehaviorWithPreconcurrency(DiagnosticBehavior::Warning,
+          .limitBehaviorWithPreconcurrency(behavior,
                                            /*preconcurrency*/ true);
       return;
+    }
 
     case MatchOutcome::WrongImplicitObjCName:
     case MatchOutcome::WrongExplicitObjCName: {

test/Concurrency/sendable_objc_attr_in_type_context_swift5.swift

@@ -172,8 +172,7 @@ class TestConformanceWithoutStripping : InnerSendableTypes {
   @objc public required init(callback: @escaping () -> Void) {}
   // expected-error@-1 {{initializer 'init(callback:)' should not be 'required' to match initializer declared by the header}}
 
-  @objc func compute(completionHandler: @escaping () -> Void) {}
-  // expected-warning@-1 {{sendability of function types in instance method 'compute(completionHandler:)' of type '(@escaping () -> Void) -> ()' does not match type '(@escaping @Sendable () -> Void) -> Void' declared by the header}}
+  @objc func compute(completionHandler: @escaping () -> Void) {} // Ok (no warnings with minimal checking)
 }
 
 // Methods deliberately has no `@Sendable` to make sure that

test/Concurrency/sendable_objc_attr_in_type_context_swift5_strict.swift

@@ -65,6 +65,11 @@ void doSomethingConcurrently(__attribute__((noescape)) void SWIFT_SENDABLE (^blo
 -(void) testWithCallback:(NSString *)name handler:(MAIN_ACTOR void (^)(NSDictionary<NSString *, SWIFT_SENDABLE id> *, NSError * _Nullable))handler;
 @end
 
+@interface SwiftImpl : NSObject
+-(id)initWithCallback:  (void (^ SWIFT_SENDABLE)(void)) callback;
+-(void)computeWithCompletionHandler: (void (^)(void)) handler;
+@end
+
 #pragma clang assume_nonnull end
 
 //--- main.swift
@@ -153,3 +158,11 @@ class TestConformanceWithoutStripping : InnerSendableTypes {
   func test(withCallback name: String, handler: @escaping @MainActor ([String : any Sendable], (any Error)?) -> Void) { // Ok
   }
 }
+
+@objc @implementation extension SwiftImpl {
+  @objc public required init(callback: @escaping () -> Void) {}
+  // expected-error@-1 {{initializer 'init(callback:)' should not be 'required' to match initializer declared by the header}}
+
+  @objc func compute(completionHandler: @escaping () -> Void) {}
+  // expected-warning@-1 {{sendability of function types in instance method 'compute(completionHandler:)' of type '(@escaping () -> Void) -> ()' does not match type '(@escaping @Sendable () -> Void) -> Void' declared by the header}}
+}

test/SILGen/objc_async.swift

@@ -10,14 +10,14 @@ func testSlowServer(slowServer: SlowServer) async throws {
   // CHECK: [[RESUME_BUF:%.*]] = alloc_stack $Int
   // CHECK: [[STRINGINIT:%.*]] = function_ref @$sSS10FoundationE19_bridgeToObjectiveCSo8NSStringCyF :
   // CHECK: [[ARG:%.*]] = apply [[STRINGINIT]]
-  // CHECK: [[METHOD:%.*]] = objc_method {{.*}} $@convention(objc_method) (NSString, @convention(block) (Int) -> (), SlowServer) -> ()
+  // CHECK: [[METHOD:%.*]] = objc_method {{.*}} $@convention(objc_method) (NSString, @convention(block) @Sendable (Int) -> (), SlowServer) -> ()
   // CHECK: [[CONT:%.*]] = get_async_continuation_addr Int, [[RESUME_BUF]]
   // CHECK: [[WRAPPED:%.*]] = struct $UnsafeContinuation<Int, Never> ([[CONT]] : $Builtin.RawUnsafeContinuation)
   // CHECK: [[BLOCK_STORAGE:%.*]] = alloc_stack $@block_storage Any
   // CHECK: [[CONT_SLOT:%.*]] = project_block_storage [[BLOCK_STORAGE]]
   // CHECK: [[CONT_SLOT_ADDR:%.*]] = init_existential_addr [[CONT_SLOT]]
   // CHECK: store [[WRAPPED]] to [trivial] [[CONT_SLOT_ADDR]]
-  // CHECK: [[BLOCK_IMPL:%.*]] = function_ref @[[INT_COMPLETION_BLOCK:.*]] : $@convention(c) (@inout_aliasable @block_storage Any, Int) -> ()
+  // CHECK: [[BLOCK_IMPL:%.*]] = function_ref @[[INT_COMPLETION_BLOCK:.*]] : $@convention(c) @Sendable (@inout_aliasable @block_storage Any, Int) -> ()
   // CHECK: [[BLOCK:%.*]] = init_block_storage_header [[BLOCK_STORAGE]] {{.*}}, invoke [[BLOCK_IMPL]]
   // CHECK: apply [[METHOD]]([[ARG]], [[BLOCK]], %0)
   // CHECK: [[COPY:%.*]] = copy_value [[ARG]]
@@ -33,14 +33,14 @@ func testSlowServer(slowServer: SlowServer) async throws {
   let _: Int = await slowServer.doSomethingSlowNullably("mail")
 
   // CHECK: [[RESUME_BUF:%.*]] = alloc_stack $String
-  // CHECK: [[METHOD:%.*]] = objc_method {{.*}} $@convention(objc_method) (@convention(block) (Optional<NSString>, Optional<NSError>) -> (), SlowServer) -> ()
+  // CHECK: [[METHOD:%.*]] = objc_method {{.*}} $@convention(objc_method) (@convention(block) @Sendable (Optional<NSString>, Optional<NSError>) -> (), SlowServer) -> ()
   // CHECK: [[CONT:%.*]] = get_async_continuation_addr [throws] String, [[RESUME_BUF]]
   // CHECK: [[WRAPPED:%.*]] = struct $UnsafeContinuation<String, any Error> ([[CONT]] : $Builtin.RawUnsafeContinuation)
   // CHECK: [[BLOCK_STORAGE:%.*]] = alloc_stack $@block_storage Any
   // CHECK: [[CONT_SLOT:%.*]] = project_block_storage [[BLOCK_STORAGE]]
   // CHECK: [[CONT_SLOT_ADDR:%.*]] = init_existential_addr [[CONT_SLOT]]
   // CHECK: store [[WRAPPED]] to [trivial] [[CONT_SLOT_ADDR]]
-  // CHECK: [[BLOCK_IMPL:%.*]] = function_ref @[[STRING_COMPLETION_THROW_BLOCK:.*]] : $@convention(c) (@inout_aliasable @block_storage Any, Optional<NSString>, Optional<NSError>) -> ()
+  // CHECK: [[BLOCK_IMPL:%.*]] = function_ref @[[STRING_COMPLETION_THROW_BLOCK:.*]] : $@convention(c) @Sendable (@inout_aliasable @block_storage Any, Optional<NSString>, Optional<NSError>) -> ()
   // CHECK: [[BLOCK:%.*]] = init_block_storage_header [[BLOCK_STORAGE]] {{.*}}, invoke [[BLOCK_IMPL]]
   // CHECK: apply [[METHOD]]([[BLOCK]], %0)
   // CHECK: await_async_continuation [[CONT]] {{.*}}, resume [[RESUME:bb[0-9]+]], error [[ERROR:bb[0-9]+]]
@@ -50,18 +50,18 @@ func testSlowServer(slowServer: SlowServer) async throws {
   // CHECK: dealloc_stack [[RESUME_BUF]]
   let _: String = try await slowServer.findAnswer()
 
-  // CHECK: objc_method {{.*}} $@convention(objc_method) (NSString, @convention(block) () -> (), SlowServer) -> ()
-  // CHECK: [[BLOCK_IMPL:%.*]] = function_ref @[[VOID_COMPLETION_BLOCK:.*]] : $@convention(c) (@inout_aliasable @block_storage Any) -> ()
+  // CHECK: objc_method {{.*}} $@convention(objc_method) (NSString, @convention(block) @Sendable () -> (), SlowServer) -> ()
+  // CHECK: [[BLOCK_IMPL:%.*]] = function_ref @[[VOID_COMPLETION_BLOCK:.*]] : $@convention(c) @Sendable (@inout_aliasable @block_storage Any) -> ()
   await slowServer.serverRestart("somewhere")
 
-  // CHECK: function_ref @[[STRING_NONZERO_FLAG_THROW_BLOCK:.*]] : $@convention(c) (@inout_aliasable @block_storage Any, {{.*}}Bool, Optional<NSString>, Optional<NSError>) -> ()
+  // CHECK: function_ref @[[STRING_NONZERO_FLAG_THROW_BLOCK:.*]] : $@convention(c) @Sendable (@inout_aliasable @block_storage Any, {{.*}}Bool, Optional<NSString>, Optional<NSError>) -> ()
   let _: String = try await slowServer.doSomethingFlaggy()
-  // CHECK: function_ref @[[STRING_ZERO_FLAG_THROW_BLOCK:.*]] : $@convention(c) (@inout_aliasable @block_storage Any, Optional<NSString>, {{.*}}Bool, Optional<NSError>) -> ()
+  // CHECK: function_ref @[[STRING_ZERO_FLAG_THROW_BLOCK:.*]] : $@convention(c) @Sendable (@inout_aliasable @block_storage Any, Optional<NSString>, {{.*}}Bool, Optional<NSError>) -> ()
   let _: String = try await slowServer.doSomethingZeroFlaggy()
-  // CHECK: function_ref @[[STRING_STRING_ZERO_FLAG_THROW_BLOCK:.*]] : $@convention(c) (@inout_aliasable @block_storage Any, {{.*}}Bool, Optional<NSString>, Optional<NSError>, Optional<NSString>) -> ()
+  // CHECK: function_ref @[[STRING_STRING_ZERO_FLAG_THROW_BLOCK:.*]] : $@convention(c) @Sendable (@inout_aliasable @block_storage Any, {{.*}}Bool, Optional<NSString>, Optional<NSError>, Optional<NSString>) -> ()
   let _: (String, String) = try await slowServer.doSomethingMultiResultFlaggy()
 
-  // CHECK: [[BLOCK_IMPL:%.*]] = function_ref @[[NSSTRING_INT_THROW_COMPLETION_BLOCK:.*]] : $@convention(c) (@inout_aliasable @block_storage Any, Optional<NSString>, Int, Optional<NSError>) -> ()
+  // CHECK: [[BLOCK_IMPL:%.*]] = function_ref @[[NSSTRING_INT_THROW_COMPLETION_BLOCK:.*]] : $@convention(c) @Sendable (@inout_aliasable @block_storage Any, Optional<NSString>, Int, Optional<NSError>) -> ()
   let (_, _): (String, Int) = try await slowServer.findMultipleAnswers()
 
   let (_, _): (Bool, Bool) = try await slowServer.findDifferentlyFlavoredBooleans()
@@ -189,14 +189,14 @@ func testSlowServerFromMain(slowServer: SlowServer) async throws {
   // CHECK: [[RESUME_BUF:%.*]] = alloc_stack $Int
   // CHECK: [[STRINGINIT:%.*]] = function_ref @$sSS10FoundationE19_bridgeToObjectiveCSo8NSStringCyF :
   // CHECK: [[ARG:%.*]] = apply [[STRINGINIT]]
-  // CHECK: [[METHOD:%.*]] = objc_method {{.*}} $@convention(objc_method) (NSString, @convention(block) (Int) -> (), SlowServer) -> ()
+  // CHECK: [[METHOD:%.*]] = objc_method {{.*}} $@convention(objc_method) (NSString, @convention(block) @Sendable (Int) -> (), SlowServer) -> ()
   // CHECK: [[CONT:%.*]] = get_async_continuation_addr Int, [[RESUME_BUF]]
   // CHECK: [[WRAPPED:%.*]] = struct $UnsafeContinuation<Int, Never> ([[CONT]] : $Builtin.RawUnsafeContinuation)
   // CHECK: [[BLOCK_STORAGE:%.*]] = alloc_stack $@block_storage Any
   // CHECK: [[CONT_SLOT:%.*]] = project_block_storage [[BLOCK_STORAGE]]
   // CHECK: [[CONT_SLOT_ANY:%.*]] = init_existential_addr [[CONT_SLOT]]
   // CHECK: store [[WRAPPED]] to [trivial] [[CONT_SLOT_ANY]]
-  // CHECK: [[BLOCK_IMPL:%.*]] = function_ref @[[INT_COMPLETION_BLOCK:.*]] : $@convention(c) (@inout_aliasable @block_storage Any, Int) -> ()
+  // CHECK: [[BLOCK_IMPL:%.*]] = function_ref @[[INT_COMPLETION_BLOCK:.*]] : $@convention(c) @Sendable (@inout_aliasable @block_storage Any, Int) -> ()
   // CHECK: [[BLOCK:%.*]] = init_block_storage_header [[BLOCK_STORAGE]] {{.*}}, invoke [[BLOCK_IMPL]]
   // CHECK: apply [[METHOD]]([[ARG]], [[BLOCK]], %0)
   // CHECK: [[COPY:%.*]] = copy_value [[ARG]]
@@ -223,10 +223,10 @@ func testThrowingMethodFromMain(slowServer: SlowServer) async -> String {
 // CHECK:  [[PROJECTED:%.*]] = project_block_storage [[STORE_ALLOC]] : $*@block_storage
 // CHECK:  [[PROJECTED_ANY:%.*]] = init_existential_addr [[PROJECTED]]
 // CHECK:  store [[CONT]] to [trivial] [[PROJECTED_ANY]]
-// CHECK:  [[INVOKER:%.*]] = function_ref @$sSo8NSStringCSgSo7NSErrorCSgIeyByy_SSTz_
+// CHECK:  [[INVOKER:%.*]] = function_ref @$sSo8NSStringCSgSo7NSErrorCSgIeyBhyy_SSTz_
 // CHECK:  [[BLOCK:%.*]] = init_block_storage_header [[STORE_ALLOC]] {{.*}}, invoke [[INVOKER]]
 // CHECK:  [[OPTIONAL_BLK:%.*]] = enum {{.*}}, #Optional.some!enumelt, [[BLOCK]]
-// CHECK:  apply [[METH]]([[STRING_ARG]], [[OPTIONAL_BLK]], {{%.*}}) : $@convention(objc_method) (NSString, Optional<@convention(block) (Optional<NSString>, Optional<NSError>) -> ()>, SlowServer) -> ()
+// CHECK:  apply [[METH]]([[STRING_ARG]], [[OPTIONAL_BLK]], {{%.*}}) : $@convention(objc_method) (NSString, Optional<@convention(block) @Sendable (Optional<NSString>, Optional<NSError>) -> ()>, SlowServer) -> ()
 // CHECK:  [[STRING_ARG_COPY:%.*]] = copy_value [[STRING_ARG]] : $NSString
 // CHECK:  dealloc_stack [[STORE_ALLOC]] : $*@block_storage Any
 // CHECK:  destroy_value [[STRING_ARG]] : $NSString