Merge pull request #83136 from hborla/invalid-isolated-conformance-downgrade

hborla · web-flow · commit 9214b0c6f171 · 2025-07-17T16:38:51.000-07:00
[Concurrency] Downgrade isolated conformances to `SendableMetatype` protocols to a warning for implicitly `@preconcurrency` protocols.
diff --git a/lib/Sema/TypeCheckConcurrency.cpp b/lib/Sema/TypeCheckConcurrency.cpp
@@ -8343,6 +8343,7 @@ RawConformanceIsolationRequest::evaluate(
       if (proto->inheritsFrom(sendableMetatype)) {
         bool isPreconcurrency = moduleImportForPreconcurrency(
             proto, conformance->getDeclContext()) != nullptr;
+        isPreconcurrency |= proto->preconcurrency();
         ctx.Diags.diagnose(
             conformance->getLoc(),
             diag::isolated_conformance_to_sendable_metatype,
diff --git a/test/Concurrency/sendable_objc_attr_in_type_context_swift5.swift b/test/Concurrency/sendable_objc_attr_in_type_context_swift5.swift
@@ -211,3 +211,7 @@ extension TestDR {
   @_dynamicReplacement(for: test(completion:))
   func __replaceObjCFunc(_: @escaping () -> Void) {} // Ok
 }
+
+@MainActor
+class InvalidIsolated: NSObject, @MainActor P {}
+// expected-warning@-1 {{cannot form main actor-isolated conformance of 'InvalidIsolated' to SendableMetatype-inheriting protocol 'P'}}

Original file line number	Diff line number	Diff line change
`@@ -211,3 +211,7 @@ extension TestDR {`
`211`	`211`	`@_dynamicReplacement(for: test(completion:))`
`212`	`212`	`func __replaceObjCFunc(_: @escaping () -> Void) {} // Ok`
`213`	`213`	`}`
	`214`	`+`
	`215`	`+@MainActor`
	`216`	`+class InvalidIsolated: NSObject, @MainActor P {}`
	`217`	`+// expected-warning@-1 {{cannot form main actor-isolated conformance of 'InvalidIsolated' to SendableMetatype-inheriting protocol 'P'}}`