[ClangImporter] Account for Sendable attributes on generic parameter requirements

Author: xedin

lib/ClangImporter/ImportDecl.cpp

@@ -7308,8 +7308,14 @@ llvm::Optional<GenericParamList *> SwiftDeclConverter::importObjCGenericParams(
     SmallVector<InheritedEntry, 1> inherited;
     if (objcGenericParam->hasExplicitBound()) {
       assert(!objcGenericParam->getUnderlyingType().isNull());
-      auto clangBound = objcGenericParam->getUnderlyingType()
+      auto underlyingTy = objcGenericParam->getUnderlyingType();
+      auto clangBound = underlyingTy
                             ->castAs<clang::ObjCObjectPointerType>();
+
+      ImportTypeAttrs attrs;
+      getConcurrencyAttrs(Impl.SwiftContext, ImportTypeKind::Abstract, attrs,
+                          underlyingTy);
+
       if (clangBound->getInterfaceDecl()) {
         auto unqualifiedClangBound =
             clangBound->stripObjCKindOfTypeAndQuals(Impl.getClangASTContext());
@@ -7324,6 +7330,15 @@ llvm::Optional<GenericParamList *> SwiftDeclConverter::importObjCGenericParams(
         }
         inherited.push_back(TypeLoc::withoutLoc(superclassType));
       }
+
+      if (attrs.contains(ImportTypeAttr::Sendable)) {
+        if (auto *sendable =
+                Impl.SwiftContext.getProtocol(KnownProtocolKind::Sendable)) {
+          inherited.push_back(
+              TypeLoc::withoutLoc(sendable->getDeclaredInterfaceType()));
+        }
+      }
+
       for (clang::ObjCProtocolDecl *clangProto : clangBound->quals()) {
         ProtocolDecl *proto = castIgnoringCompatibilityAlias<ProtocolDecl>(
             Impl.importDecl(clangProto, getActiveSwiftVersion()));

lib/ClangImporter/ImportType.cpp

@@ -1991,7 +1991,9 @@ class GetSendableType :
   VISIT(ModuleType, pass)
   VISIT(DynamicSelfType, pass)
 
-  NEVER_VISIT(SubstitutableType)
+  // Ignore attributes placed on generic parameter references and
+  // other substitutable types.
+  VISIT(SubstitutableType, pass)
   NEVER_VISIT(DependentMemberType)
 
   Result visitAnyFunctionType(AnyFunctionType *ty) {

test/Concurrency/sendable_objc_attr_in_type_context.swift

@@ -21,6 +21,17 @@
 @interface MyValue : NSObject
 @end
 
+SWIFT_SENDABLE
+@protocol P <NSObject>
+@end
+
+@interface SendableValue : NSObject<P>
+@end
+
+SWIFT_SENDABLE
+@interface SendableMyValue : MyValue
+@end
+
 typedef void (^CompletionHandler)(void (^ SWIFT_SENDABLE)(void)) SWIFT_SENDABLE;
 
 @interface Test : NSObject
@@ -36,6 +47,14 @@ typedef void (^CompletionHandler)(void (^ SWIFT_SENDABLE)(void)) SWIFT_SENDABLE;
 // Placement of SWIFT_SENDABLE matters here
 void doSomethingConcurrently(__attribute__((noescape)) void SWIFT_SENDABLE (^block)(void));
 
+@interface TestWithSendableID<T: SWIFT_SENDABLE id> : NSObject
+-(void) add: (T) object;
+@end
+
+@interface TestWithSendableSuperclass<T: MyValue *SWIFT_SENDABLE> : NSObject
+-(void) add: (T) object;
+@end
+
 #pragma clang assume_nonnull end
 
 //--- main.swift
@@ -72,4 +91,16 @@ func test_sendable_attr_in_type_context(test: Test) {
   test.withAliasCompletionHandler { callback in
     doSomethingConcurrently(callback) // Ok
   }
+
+  _ = TestWithSendableID<SendableValue>() // Ok
+
+  // TOOD(diagnostics): Duplicate diagnostics
+  TestWithSendableID().add(MyValue())
+  // expected-warning@-1 3 {{type 'MyValue' does not conform to the 'Sendable' protocol}}
+
+  TestWithSendableSuperclass().add(SendableMyValue()) // Ok
+
+  // TOOD(diagnostics): Duplicate diagnostics
+  TestWithSendableSuperclass().add(MyValue())
+  // expected-warning@-1 3 {{type 'MyValue' does not conform to the 'Sendable' protocol}}
 }