Merge pull request swiftlang#36881 from egorzhdan/cxx-lookup-fix

C++ Interop: fix crash for Swift extensions of C++ classes declared in namespaces

Author: egorzhdan

lib/AST/ASTMangler.cpp

@@ -2303,9 +2303,9 @@ void ASTMangler::appendAnyGenericType(const GenericTypeDecl *decl) {
                isa<clang::ObjCCompatibleAliasDecl>(namedDecl)) {
       appendOperator("a");
     } else if (isa<clang::NamespaceDecl>(namedDecl)) {
-      // Note: Namespaces are not really structs, but since namespaces are
+      // Note: Namespaces are not really enums, but since namespaces are
       // imported as enums, be consistent.
-      appendOperator("V");
+      appendOperator("O");
     } else {
       llvm_unreachable("unknown imported Clang type");
     }

lib/ClangImporter/ClangImporter.cpp

@@ -2732,36 +2732,41 @@ void ClangImporter::lookupTypeDecl(
   clang::DeclarationName clangName(
       &Impl.Instance->getASTContext().Idents.get(rawName));
 
-  clang::Sema::LookupNameKind lookupKind;
+  SmallVector<clang::Sema::LookupNameKind, 1> lookupKinds;
   switch (kind) {
   case ClangTypeKind::Typedef:
-    lookupKind = clang::Sema::LookupOrdinaryName;
+    lookupKinds.push_back(clang::Sema::LookupOrdinaryName);
     break;
   case ClangTypeKind::Tag:
-    lookupKind = clang::Sema::LookupTagName;
+    lookupKinds.push_back(clang::Sema::LookupTagName);
+    lookupKinds.push_back(clang::Sema::LookupNamespaceName);
     break;
   case ClangTypeKind::ObjCProtocol:
-    lookupKind = clang::Sema::LookupObjCProtocolName;
+    lookupKinds.push_back(clang::Sema::LookupObjCProtocolName);
     break;
   }
 
   // Perform name lookup into the global scope.
   auto &sema = Impl.Instance->getSema();
-  clang::LookupResult lookupResult(sema, clangName, clang::SourceLocation(),
-                                   lookupKind);
   bool foundViaClang = false;
-  if (!Impl.DisableSourceImport &&
-      sema.LookupName(lookupResult, /*Scope=*/nullptr)) {
-    for (auto clangDecl : lookupResult) {
-      if (!isa<clang::TypeDecl>(clangDecl) &&
-          !isa<clang::ObjCContainerDecl>(clangDecl) &&
-          !isa<clang::ObjCCompatibleAliasDecl>(clangDecl)) {
-        continue;
-      }
-      auto *imported = Impl.importDecl(clangDecl, Impl.CurrentVersion);
-      if (auto *importedType = dyn_cast_or_null<TypeDecl>(imported)) {
-        foundViaClang = true;
-        receiver(importedType);
+
+  for (auto lookupKind : lookupKinds) {
+    clang::LookupResult lookupResult(sema, clangName, clang::SourceLocation(),
+                                     lookupKind);
+    if (!Impl.DisableSourceImport &&
+        sema.LookupName(lookupResult, /*Scope=*/ sema.TUScope)) {
+      for (auto clangDecl : lookupResult) {
+        if (!isa<clang::TypeDecl>(clangDecl) &&
+            !isa<clang::NamespaceDecl>(clangDecl) &&
+            !isa<clang::ObjCContainerDecl>(clangDecl) &&
+            !isa<clang::ObjCCompatibleAliasDecl>(clangDecl)) {
+          continue;
+        }
+        auto *imported = Impl.importDecl(clangDecl, Impl.CurrentVersion);
+        if (auto *importedType = dyn_cast_or_null<TypeDecl>(imported)) {
+          foundViaClang = true;
+          receiver(importedType);
+        }
       }
     }
   }

test/ClangImporter/cxx_interop_ir.swift

@@ -9,17 +9,17 @@ func indirectUsage() {
   useT(makeT())
 }
 
-// CHECK-LABEL: define hidden swiftcc %swift.type* @"$s6cxx_ir14reflectionInfo3argypXpSo2nsV10CXXInteropE1TV_tF"
-// CHECK: %0 = call swiftcc %swift.metadata_response @"$sSo2nsV10CXXInteropE1TVMa"({{i64|i32}} 0)
+// CHECK-LABEL: define hidden swiftcc %swift.type* @"$s6cxx_ir14reflectionInfo3argypXpSo2nsO10CXXInteropE1TV_tF"
+// CHECK: %0 = call swiftcc %swift.metadata_response @"$sSo2nsO10CXXInteropE1TVMa"({{i64|i32}} 0)
 func reflectionInfo(arg: namespacedT) -> Any.Type {
   return type(of: arg)
 }
 
-// CHECK: define hidden swiftcc void @"$s6cxx_ir24namespaceManglesIntoName3argySo2nsV10CXXInteropE1TV_tF"
+// CHECK: define hidden swiftcc void @"$s6cxx_ir24namespaceManglesIntoName3argySo2nsO10CXXInteropE1TV_tF"
 func namespaceManglesIntoName(arg: namespacedT) {
 }
 
-// CHECK: define hidden swiftcc void @"$s6cxx_ir42namespaceManglesIntoNameForUsingShadowDecl3argySo2nsV10CXXInteropE14NamespacedTypeV_tF"
+// CHECK: define hidden swiftcc void @"$s6cxx_ir42namespaceManglesIntoNameForUsingShadowDecl3argySo2nsO10CXXInteropE14NamespacedTypeV_tF"
 func namespaceManglesIntoNameForUsingShadowDecl(arg: NamespacedType) {
 }
 

test/Interop/Cxx/class/Inputs/extensions.h

@@ -0,0 +1,14 @@
+#ifndef TEST_INTEROP_CXX_CLASS_INPUTS_EXTENSIONS_H
+#define TEST_INTEROP_CXX_CLASS_INPUTS_EXTENSIONS_H
+
+namespace Outer {
+namespace Space {
+
+struct Foo {
+  int a;
+};
+
+}
+}
+
+#endif //TEST_INTEROP_CXX_CLASS_INPUTS_EXTENSIONS_H

test/Interop/Cxx/class/Inputs/module.modulemap

@@ -23,6 +23,11 @@ module Destructors {
   requires cplusplus
 }
 
+module Extensions {
+  header "extensions.h"
+  requires cplusplus
+}
+
 module LoadableTypes {
   header "loadable-types.h"
   requires cplusplus

test/Interop/Cxx/class/extensions-executable.swift

@@ -0,0 +1,18 @@
+// RUN: %target-run-simple-swift(-I %S/Inputs/ -Xfrontend -enable-cxx-interop)
+// REQUIRES: executable_test
+
+import StdlibUnittest
+import Extensions
+
+var CxxClassExtensionsTestSuite = TestSuite("CxxClassExtensions")
+
+extension Outer.Space.Foo {
+  func bar() -> Int32 { return a + 1 }
+}
+
+CxxClassExtensionsTestSuite.test("calling extension method") {
+  var foo = Outer.Space.Foo(a: 123)
+  expectEqual(124, foo.bar())
+}
+
+runAllTests()

test/Interop/Cxx/class/extensions-irgen.swift

@@ -0,0 +1,16 @@
+// RUN: %target-swift-emit-ir %s -I %S/Inputs -enable-cxx-interop | %FileCheck %s
+//
+// We can't yet call member functions correctly on Windows (SR-13129).
+// XFAIL: OS=windows-msvc
+
+import Extensions
+
+extension Outer.Space.Foo {
+  func foo() {}
+}
+
+Outer.Space.Foo().foo()
+
+// CHECK: call swiftcc void @"$sSo5OuterO5SpaceO10ExtensionsE3FooV4mainE3fooyyF"
+
+// CHECK: define hidden swiftcc void @"$sSo5OuterO5SpaceO10ExtensionsE3FooV4mainE3fooyyF"

test/Interop/Cxx/class/extensions-typechecker.swift

@@ -0,0 +1,16 @@
+// RUN: %target-typecheck-verify-swift -I %S/Inputs -enable-cxx-interop
+
+import Extensions
+
+extension Outer.Space.Foo {
+  func bar() -> Int32 { return a }
+}
+
+extension Outer.Space.Foo: ExpressibleByIntegerLiteral {
+  public init(integerLiteral value: IntegerLiteralType) {
+    self.init(a: Int32(value))
+  }
+}
+
+var it: Outer.Space.Foo = 123
+let res = it.bar()