Merge pull request #68953 from tshortli/no-unavailable-stub-for-clang-enums

SILGen: Don't stub unavailable raw value initializers for clang enums

Author: tshortli

lib/AST/Availability.cpp

@@ -23,6 +23,7 @@
 #include "swift/AST/TypeWalker.h"
 #include "swift/AST/Types.h"
 #include "swift/Basic/Platform.h"
+#include "swift/ClangImporter/ClangModule.h"
 #include <map>
 
 using namespace swift;
@@ -312,7 +313,7 @@ bool Decl::isAvailableDuringLowering() const {
       UnavailableDeclOptimization::Complete)
     return true;
 
-  if (hasClangNode())
+  if (isa<ClangModuleUnit>(getDeclContext()->getModuleScopeContext()))
     return true;
 
   return !isUnconditionallyUnavailable(this);
@@ -325,6 +326,9 @@ bool Decl::requiresUnavailableDeclABICompatibilityStubs() const {
       UnavailableDeclOptimization::Stub)
     return false;
 
+  if (isa<ClangModuleUnit>(getDeclContext()->getModuleScopeContext()))
+    return false;
+
   return isUnconditionallyUnavailable(this);
 }
 

test/SILGen/unavailable_clang_enum_typedef.swift

@@ -0,0 +1,23 @@
+// RUN: %empty-directory(%t)
+// RUN: split-file %s %t
+// RUN: %target-swift-emit-silgen %t/Overlay.swift -I %t -import-objc-header %t/MyOptions.h -unavailable-decl-optimization=none | %FileCheck %t/Overlay.swift
+// RUN: %target-swift-emit-silgen %t/Overlay.swift -I %t -import-objc-header %t/MyOptions.h -unavailable-decl-optimization=stub | %FileCheck %t/Overlay.swift
+// RUN: %target-swift-emit-silgen %t/Overlay.swift -I %t -import-objc-header %t/MyOptions.h -unavailable-decl-optimization=complete | %FileCheck %t/Overlay.swift
+
+//--- MyOptions.h
+
+__attribute__((availability(swift, unavailable, message="Unavailable in Swift")))
+typedef enum : int {
+  SomeOption,
+} MyOptions;
+
+typedef MyOptions MyOptionsTypedef;
+
+//--- Overlay.swift
+
+// This really shouldn't be allowed, but it is.
+let _ = MyOptionsTypedef(rawValue: 1)
+
+// CHECK-LABEL: sil shared [transparent] [serialized]{{.*}} @$sSo9MyOptionsa8rawValueABs5Int32V_tcfC : $@convention(method) (Int32, @thin MyOptions.Type) -> MyOptions {
+// CHECK-NOT:     ss31_diagnoseUnavailableCodeReacheds5NeverOyFTwb
+// CHECK:       } // end sil function '$sSo9MyOptionsa8rawValueABs5Int32V_tcfC'