Merge pull request #75267 from kavon/revert-backcompat-removal

Revert "NCGenerics: remove the reverse-condfail workaround"

Author: kavon

include/swift/Basic/Features.def

@@ -393,6 +393,8 @@ EXPERIMENTAL_FEATURE(DebugDescriptionMacro, true)
 
 EXPERIMENTAL_FEATURE(ReinitializeConsumeInMultiBlockDefer, false)
 
+EXPERIMENTAL_FEATURE(SE427NoInferenceOnExtension, false)
+
 #undef EXPERIMENTAL_FEATURE_EXCLUDED_FROM_MODULE_INTERFACE
 #undef EXPERIMENTAL_FEATURE
 #undef UPCOMING_FEATURE

lib/AST/FeatureSet.cpp

@@ -220,6 +220,7 @@ UNINTERESTING_FEATURE(CImplementation)
 UNINTERESTING_FEATURE(Sensitive)
 UNINTERESTING_FEATURE(DebugDescriptionMacro)
 UNINTERESTING_FEATURE(ReinitializeConsumeInMultiBlockDefer)
+UNINTERESTING_FEATURE(SE427NoInferenceOnExtension)
 
 // ----------------------------------------------------------------------------
 // MARK: - FeatureSet

lib/Sema/TypeCheckGeneric.cpp

@@ -788,6 +788,15 @@ GenericSignatureRequest::evaluate(Evaluator &evaluator,
     // to invertible protocols. This forces people to write out the conditions.
     inferInvertibleReqs = !ext->isAddingConformanceToInvertible();
 
+    // FIXME: to workaround a reverse condfail, always infer the requirements if
+    //  the extension is in a swiftinterface file. This is temporary and should
+    //  be removed soon. (rdar://130424971)
+    if (auto *sf = ext->getOutermostParentSourceFile()) {
+      if (sf->Kind == SourceFileKind::Interface
+          && !ctx.LangOpts.hasFeature(Feature::SE427NoInferenceOnExtension))
+        inferInvertibleReqs = true;
+    }
+
     collectAdditionalExtensionRequirements(ext->getExtendedType(), extraReqs);
 
     auto *extendedNominal = ext->getExtendedNominal();

test/ModuleInterface/noncopyable_generics.swift

@@ -1,15 +1,20 @@
 // RUN: %empty-directory(%t)
 
+// Due to SE427NoInferenceOnExtension not being in production
+// REQUIRES: asserts
+
 // RUN: %target-swift-frontend -swift-version 5 -enable-library-evolution -emit-module \
 // RUN:     -enable-experimental-feature SuppressedAssociatedTypes \
 // RUN:     -enable-experimental-feature NonescapableTypes \
+// RUN:     -enable-experimental-feature SE427NoInferenceOnExtension \
 // RUN:     -o %t/NoncopyableGenerics_Misc.swiftmodule \
 // RUN:     -emit-module-interface-path %t/NoncopyableGenerics_Misc.swiftinterface \
 // RUN:     %S/Inputs/NoncopyableGenerics_Misc.swift
 
 // RUN: %target-swift-frontend -swift-version 5 -enable-library-evolution -emit-module \
 // RUN:     -enable-experimental-feature SuppressedAssociatedTypes \
 // RUN:     -enable-experimental-feature NonescapableTypes \
+// RUN:     -enable-experimental-feature SE427NoInferenceOnExtension \
 // RUN:     -o %t/Swiftskell.swiftmodule \
 // RUN:     -emit-module-interface-path %t/Swiftskell.swiftinterface \
 // RUN:     %S/../Inputs/Swiftskell.swift
@@ -24,16 +29,19 @@
 // RUN: %target-swift-frontend -compile-module-from-interface \
 // RUN:     -enable-experimental-feature SuppressedAssociatedTypes \
 // RUN:     -enable-experimental-feature NonescapableTypes \
+// RUN:     -enable-experimental-feature SE427NoInferenceOnExtension \
 // RUN:    %t/NoncopyableGenerics_Misc.swiftinterface -o %t/NoncopyableGenerics_Misc.swiftmodule
 
 // RUN: %target-swift-frontend -compile-module-from-interface \
 // RUN:     -enable-experimental-feature SuppressedAssociatedTypes \
 // RUN:     -enable-experimental-feature NonescapableTypes \
+// RUN:     -enable-experimental-feature SE427NoInferenceOnExtension \
 // RUN:    %t/Swiftskell.swiftinterface -o %t/Swiftskell.swiftmodule
 
 // RUN: %target-swift-frontend -emit-silgen -I %t %s \
 // RUN:     -enable-experimental-feature SuppressedAssociatedTypes \
 // RUN:    -enable-experimental-feature NonescapableTypes \
+// RUN:     -enable-experimental-feature SE427NoInferenceOnExtension \
 // RUN:    -o %t/final.silgen
 
 // RUN: %FileCheck %s --check-prefix=CHECK-SILGEN < %t/final.silgen

test/ModuleInterface/noncopyable_generics_interface_extensions.swift

@@ -0,0 +1,32 @@
+// RUN: %empty-directory(%t)
+// RUN: split-file %s %t
+// RUN: %target-swift-typecheck-module-from-interface(%t/bug.swiftinterface) -I %t
+
+//--- bug.swiftinterface
+
+// swift-interface-format-version: 1.0
+// swift-compiler-version: Apple Swift version 6.0 effective-5.10 (swiftlang-6.0.0.4.52 clang-1600.0.21.1.3)
+// swift-module-flags: -enable-objc-interop -enable-library-evolution -module-name bug
+import Swift
+import _Concurrency
+import _StringProcessing
+import _SwiftConcurrencyShims
+#if compiler(>=5.3) && $NoncopyableGenerics
+public enum Maybe<Wrapped> : ~Swift.Copyable where Wrapped : ~Copyable {
+  case just(Wrapped)
+  case none
+}
+#else
+public enum Maybe<Wrapped> {
+  case just(Wrapped)
+  case none
+}
+#endif
+#if compiler(>=5.3) && $NoncopyableGenerics
+extension bug.Maybe : Swift.Copyable {
+}
+#else
+extension bug.Maybe {
+}
+#endif
+