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[SE-0470] Enable isolated conformances by default
The IsolatedConformances feature moves to a normal, supported feature. Remove all of the experimental-feature flags on test cases and such. The InferIsolatedConformances feature moves to an upcoming feature for Swift 7. This should become an adoptable feature, adding "nonisolated" where needed.
1 parent e8b3065 commit 3380331

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+68
-76
lines changed

‎CHANGELOG.md

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@@ -32,6 +32,34 @@
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strategy, given that the code would eventually become ambiguous anyways when
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the deployment target is raised.
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* [SE-0470][]:
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A protocol conformance can be isolated to a specific global actor, meaning that the conformance can only be used by code running on that actor. Isolated conformances are expressed by specifying the global actor on the conformance itself:
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```swift
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protocol P {
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func f()
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}
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@MainActor
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class MyType: @MainActor P {
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/*@MainActor*/ func f() {
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// must be called on the main actor
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}
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}
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```
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Swift will produce diagnostics if the conformance is directly accessed in code that isn't guaranteed to execute in the same global actor. For example:
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```swift
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func acceptP<T: P>(_ value: T) { }
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/*nonisolated*/ func useIsolatedConformance(myType: MyType) {
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acceptP(myType) // error: main actor-isolated conformance of 'MyType' to 'P' cannot be used in nonisolated context
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}
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```
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To address such issues, only use an isolated conformance from code that executes on the same global actor.
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* [SE-0419][]:
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Introduced the new `Runtime` module, which contains a public API that can
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generate backtraces, presently supported on macOS and Linux. Capturing a
@@ -10759,6 +10787,7 @@ using the `.dynamicType` member to retrieve the type of an expression should mig
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[SE-0442]: https://github.com/swiftlang/swift-evolution/blob/main/proposals/0442-allow-taskgroup-childtaskresult-type-to-be-inferred.md
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[SE-0444]: https://github.com/swiftlang/swift-evolution/blob/main/proposals/0444-member-import-visibility.md
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[SE-0458]: https://github.com/swiftlang/swift-evolution/blob/main/proposals/0458-strict-memory-safety.md
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[SE-0470]: https://github.com/swiftlang/swift-evolution/blob/main/proposals/0470-isolated-conformances.md
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[#64927]: <https://github.com/apple/swift/issues/64927>
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[#42697]: <https://github.com/apple/swift/issues/42697>
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[#42728]: <https://github.com/apple/swift/issues/42728>

‎include/swift/AST/DiagnosticsSema.def

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@@ -8526,10 +8526,6 @@ ERROR(attr_abi_failable_mismatch,none,
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//===----------------------------------------------------------------------===//
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// MARK: Isolated conformances
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//===----------------------------------------------------------------------===//
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GROUPED_ERROR(isolated_conformance_experimental_feature,IsolatedConformances,
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none,
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"isolated conformances require experimental feature "
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" 'IsolatedConformances'", ())
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NOTE(note_isolate_conformance_to_global_actor,none,
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"isolate this conformance to the %select{global actor %0|main actor}1 "
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"with '@%2'", (Type, bool, StringRef))

‎include/swift/Basic/Features.def

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@@ -255,6 +255,7 @@ LANGUAGE_FEATURE(ValueGenerics, 452, "Value generics feature (integer generics)"
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LANGUAGE_FEATURE(RawIdentifiers, 451, "Raw identifiers")
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LANGUAGE_FEATURE(SendableCompletionHandlers, 463, "Objective-C completion handler parameters are imported as @Sendable")
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LANGUAGE_FEATURE(AsyncExecutionBehaviorAttributes, 0, "@concurrent and nonisolated(nonsending)")
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LANGUAGE_FEATURE(IsolatedConformances, 407, "Global-actor isolated conformances")
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// Swift 6
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UPCOMING_FEATURE(ConciseMagicFile, 274, 6)
@@ -277,6 +278,7 @@ UPCOMING_FEATURE(GlobalActorIsolatedTypesUsability, 0434, 6)
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ADOPTABLE_UPCOMING_FEATURE(ExistentialAny, 335, 7)
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UPCOMING_FEATURE(InternalImportsByDefault, 409, 7)
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UPCOMING_FEATURE(MemberImportVisibility, 444, 7)
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UPCOMING_FEATURE(InferIsolatedConformances, 470, 7)
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// Optional language features / modes
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@@ -492,12 +494,6 @@ ADOPTABLE_EXPERIMENTAL_FEATURE(AsyncCallerExecution, false)
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/// Allow custom availability domains to be defined and referenced.
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EXPERIMENTAL_FEATURE(CustomAvailability, true)
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/// Allow isolated conformances.
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EXPERIMENTAL_FEATURE(IsolatedConformances, true)
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/// Infer conformance isolation on global-actor-conforming types.
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EXPERIMENTAL_FEATURE(InferIsolatedConformances, true)
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/// Allow SwiftSettings
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EXPERIMENTAL_FEATURE(SwiftSettings, false)
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‎lib/AST/ConformanceLookup.cpp

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@@ -386,33 +386,30 @@ static ProtocolConformanceRef getBuiltinMetaTypeTypeConformance(
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// All metatypes are Copyable, Escapable, and BitwiseCopyable.
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if (auto kp = protocol->getKnownProtocolKind()) {
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switch (*kp) {
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case KnownProtocolKind::Sendable:
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case KnownProtocolKind::Sendable: {
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// Metatypes are generally Sendable, but with isolated conformances we
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// cannot assume that metatypes based on type parameters are Sendable.
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// Therefore, check for conformance to SendableMetatype.
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if (ctx.LangOpts.hasFeature(Feature::IsolatedConformances)) {
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auto sendableMetatypeProto =
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ctx.getProtocol(KnownProtocolKind::SendableMetatype);
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if (sendableMetatypeProto) {
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Type instanceType = metatypeType->getInstanceType();
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// If the instance type is a type parameter, it is not necessarily
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// Sendable. There will need to be a Sendable requirement.
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if (instanceType->isTypeParameter())
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break;
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// If the instance type conforms to SendableMetatype, then its
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// metatype is Sendable.
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auto instanceConformance = lookupConformance(
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instanceType, sendableMetatypeProto);
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if (instanceConformance.isInvalid() ||
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instanceConformance.hasMissingConformance())
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break;
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}
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// Every other metatype is Sendable.
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auto sendableMetatypeProto =
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ctx.getProtocol(KnownProtocolKind::SendableMetatype);
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if (sendableMetatypeProto) {
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Type instanceType = metatypeType->getInstanceType();
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// If the instance type is a type parameter, it is not necessarily
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// Sendable. There will need to be a Sendable requirement.
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if (instanceType->isTypeParameter())
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break;
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// If the instance type conforms to SendableMetatype, then its
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// metatype is Sendable.
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auto instanceConformance = lookupConformance(
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instanceType, sendableMetatypeProto);
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if (instanceConformance.isInvalid() ||
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instanceConformance.hasMissingConformance())
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break;
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}
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LLVM_FALLTHROUGH;
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}
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case KnownProtocolKind::Copyable:
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case KnownProtocolKind::Escapable:

‎lib/Parse/ParseType.cpp

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@@ -167,9 +167,7 @@ ParserResult<TypeRepr> Parser::parseTypeSimple(
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Diag<> MessageID, ParseTypeReason reason) {
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ParserResult<TypeRepr> ty;
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if (isParameterSpecifier() &&
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!(!Context.LangOpts.hasFeature(Feature::IsolatedConformances) &&
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Tok.isContextualKeyword("isolated"))) {
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if (isParameterSpecifier()) {
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// Type specifier should already be parsed before here. This only happens
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// for construct like 'P1 & inout P2'.
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diagnose(Tok.getLoc(), diag::attr_only_on_parameters, Tok.getRawText());

‎lib/Sema/TypeCheckConcurrency.cpp

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// FIXME: When passing to a sending parameter, should this be handled
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// by region isolation? Or should it always be handled by region
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// isolation?
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if (ctx.LangOpts.hasFeature(Feature::IsolatedConformances) &&
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(mayExecuteConcurrentlyWith(
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if (mayExecuteConcurrentlyWith(
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localFunc.getAsDeclContext(), getDeclContext()) ||
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(explicitClosure && explicitClosure->isPassedToSendingParameter()))) {
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(explicitClosure && explicitClosure->isPassedToSendingParameter())) {
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GenericSignature genericSig;
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if (auto afd = localFunc.getAbstractFunctionDecl())
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genericSig = afd->getGenericSignature();
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auto dc = rootNormal->getDeclContext();
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ASTContext &ctx = dc->getASTContext();
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if (!ctx.LangOpts.hasFeature(Feature::IsolatedConformances))
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return ActorIsolation::forNonisolated(false);
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// If the protocol itself is isolated, don't infer isolation for the
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// conformance.

‎lib/Sema/TypeCheckProtocol.cpp

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@@ -2567,13 +2567,6 @@ checkIndividualConformance(NormalProtocolConformance *conformance) {
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ComplainLoc, diag::unchecked_conformance_not_special, ProtoType);
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}
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// Complain if the global-actor-isolated conformances are not enabled.
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if (conformance->isIsolated() &&
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!Context.LangOpts.hasFeature(Feature::IsolatedConformances)) {
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Context.Diags.diagnose(
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ComplainLoc, diag::isolated_conformance_experimental_feature);
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}
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bool allowImpliedConditionalConformance = false;
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if (Proto->isSpecificProtocol(KnownProtocolKind::Sendable)) {
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// In -swift-version 5 mode, a conditional conformance to a protocol can imply
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}
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// Suggest isolating the conformance, if possible.
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if (ctx.LangOpts.hasFeature(Feature::IsolatedConformances) &&
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potentialIsolation && potentialIsolation->isGlobalActor() &&
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if (potentialIsolation && potentialIsolation->isGlobalActor() &&
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!conformance->isIsolated()) {
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bool isMainActor = false;
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Type globalActorIsolation = potentialIsolation->getGlobalActor();

‎test/Concurrency/Runtime/isolated_conformance.swift

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// RUN: %target-run-simple-swift(-enable-experimental-feature IsolatedConformances -target %target-swift-5.1-abi-triple) | %FileCheck %s
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// RUN: %target-run-simple-swift(-target %target-swift-5.1-abi-triple) | %FileCheck %s
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// REQUIRES: executable_test
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// REQUIRES: concurrency
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// REQUIRES: concurrency_runtime
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// REQUIRES: swift_feature_IsolatedConformances
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// UNSUPPORTED: back_deployment_runtime
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// FIXME: WebAssembly doesn't currently have a good way to install the

‎test/Concurrency/isolated_conformance.swift

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// RUN: %target-swift-frontend -typecheck -verify -target %target-swift-5.1-abi-triple -swift-version 5 -strict-concurrency=complete -enable-experimental-feature IsolatedConformances %s
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// RUN: %target-swift-frontend -typecheck -verify -target %target-swift-5.1-abi-triple -swift-version 5 -strict-concurrency=complete %s
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// REQUIRES: swift_feature_IsolatedConformances
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// REQUIRES: concurrency
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protocol P {

‎test/Concurrency/isolated_conformance_default_actor.swift

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// RUN: %target-swift-frontend -typecheck -verify -target %target-swift-5.1-abi-triple -swift-version 6 -enable-experimental-feature IsolatedConformances -default-isolation MainActor %s
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// RUN: %target-swift-frontend -typecheck -verify -target %target-swift-5.1-abi-triple -swift-version 6 -default-isolation MainActor %s
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// REQUIRES: swift_feature_IsolatedConformances
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// REQUIRES: concurrency
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nonisolated

‎test/Concurrency/isolated_conformance_inference.swift

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// RUN: %target-swift-frontend -typecheck -verify -target %target-swift-5.1-abi-triple -swift-version 6 -enable-experimental-feature IsolatedConformances -enable-experimental-feature InferIsolatedConformances %s
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// RUN: %target-swift-frontend -typecheck -verify -target %target-swift-5.1-abi-triple -swift-version 6 -enable-upcoming-feature InferIsolatedConformances %s
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// REQUIRES: swift_feature_IsolatedConformances
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// REQUIRES: swift_feature_InferIsolatedConformances
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// REQUIRES: concurrency
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protocol P {

‎test/Concurrency/sendable_metatype.swift

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// RUN: %target-typecheck-verify-swift -swift-version 6 -enable-experimental-feature IsolatedConformances -emit-sil -o /dev/null
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// RUN: %target-typecheck-verify-swift -swift-version 6 -emit-sil -o /dev/null
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// REQUIRES: concurrency
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// REQUIRES: swift_feature_IsolatedConformances
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protocol Q {

‎test/Concurrency/sendable_metatype_typecheck.swift

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// RUN: %target-typecheck-verify-swift -swift-version 6 -enable-experimental-feature IsolatedConformances
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// RUN: %target-typecheck-verify-swift -swift-version 6
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// REQUIRES: concurrency
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// REQUIRES: swift_feature_IsolatedConformances
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// This test checks for typecheck-only diagnostics involving non-sendable
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// metatypes.

‎test/IRGen/isolated_conformance.swift

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// RUN: %target-swift-frontend -primary-file %s -emit-ir -swift-version 6 -enable-experimental-feature IsolatedConformances | %FileCheck %s -DINT=i%target-ptrsize
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// RUN: %target-swift-frontend -primary-file %s -emit-ir -swift-version 6 | %FileCheck %s -DINT=i%target-ptrsize
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// REQUIRES: PTRSIZE=64
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// REQUIRES: concurrency
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// REQUIRES: swift_feature_IsolatedConformances
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// UNSUPPORTED: CPU=arm64e
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protocol P {

‎test/ModuleInterface/isolated_conformance.swift

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// RUN: %target-swift-frontend -typecheck -swift-version 6 -enable-library-evolution -module-name isolated_conformance -enable-experimental-feature IsolatedConformances -emit-module-interface-path - %s | %FileCheck %s
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// RUN: %target-swift-frontend -typecheck -swift-version 6 -enable-library-evolution -module-name isolated_conformance -emit-module-interface-path - %s | %FileCheck %s
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// REQUIRES: swift_feature_IsolatedConformances
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// REQUIRES: concurrency
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public protocol MyProtocol {

‎test/SILOptimizer/constant_propagation_casts_ossa.sil

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// RUN: %target-sil-opt -enable-sil-verify-all %s -diagnostic-constant-propagation -enable-experimental-feature IsolatedConformances | %FileCheck %s
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// RUN: %target-sil-opt -enable-sil-verify-all %s -diagnostic-constant-propagation | %FileCheck %s
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// REQUIRES: swift_feature_IsolatedConformances
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// REQUIRES: concurrency
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sil_stage canonical

‎test/SILOptimizer/isolated_conformances.swift

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// RUN: %empty-directory(%t)
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// RUN: %target-build-swift -parse-as-library -O %s -enable-experimental-feature IsolatedConformances -o %t/a.out
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// RUN: %target-build-swift -parse-as-library -O %s -o %t/a.out
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// RUN: %target-codesign %t/a.out
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// RUN: %target-run %t/a.out | %FileCheck %s --check-prefix=CHECK-OUTPUT
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// RUN: %target-build-swift -parse-as-library -O %s -enable-experimental-feature IsolatedConformances -Xllvm -sil-disable-pass=function-signature-opts -emit-sil | %FileCheck %s
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// RUN: %target-build-swift -parse-as-library -O %s -Xllvm -sil-disable-pass=function-signature-opts -emit-sil | %FileCheck %s
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// REQUIRES: concurrency
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// REQUIRES: executable_test
1010
// REQUIRES: concurrency_runtime
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// REQUIRES: swift_feature_IsolatedConformances
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// REQUIRES: OS=macosx || OS=linux-gnu
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// UNSUPPORTED: back_deployment_runtime

‎test/SILOptimizer/simplify_unconditional_check_cast.sil

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// RUN: %target-sil-opt -enable-sil-verify-all %s -simplification -simplify-instruction=unconditional_checked_cast -enable-experimental-feature IsolatedConformances | %FileCheck %s
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// RUN: %target-sil-opt -enable-sil-verify-all %s -simplification -simplify-instruction=unconditional_checked_cast | %FileCheck %s
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// REQUIRES: swift_feature_IsolatedConformances
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// REQUIRES: concurrency
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import Swift

‎test/Serialization/isolated_conformance.swift

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// RUN: %empty-directory(%t)
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// RUN: %target-swift-frontend -emit-module -target %target-swift-5.1-abi-triple -swift-version 6 -enable-experimental-feature IsolatedConformances -o %t/def_isolated_conformance.swiftmodule %S/Inputs/def_isolated_conformance.swift
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// RUN: %target-swift-frontend -emit-module -target %target-swift-5.1-abi-triple -swift-version 6 -o %t/def_isolated_conformance.swiftmodule %S/Inputs/def_isolated_conformance.swift
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4-
// RUN: %target-swift-frontend -typecheck -verify -target %target-swift-5.1-abi-triple -swift-version 6 -enable-experimental-feature IsolatedConformances %s -I %t
4+
// RUN: %target-swift-frontend -typecheck -verify -target %target-swift-5.1-abi-triple -swift-version 6 %s -I %t
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// REQUIRES: swift_feature_IsolatedConformances
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// REQUIRES: concurrency
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import def_isolated_conformance

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