Merge pull request #31948 from slavapestov/print-as-objc-generic-typealias-assertion-5.3

PrintAsObjC: Fix crash when printing typedef that was imported inside an Objective-C generic class [5.3]

Author: tkremenek

lib/PrintAsObjC/ModuleContentsWriter.cpp

@@ -56,7 +56,7 @@ class ReferencedTypeFinder : public TypeDeclFinder {
   Action visitTypeAliasType(TypeAliasType *aliasTy) override {
     if (aliasTy->getDecl()->hasClangNode() &&
         !aliasTy->getDecl()->isCompatibilityAlias()) {
-      assert(!aliasTy->getGenericSignature());
+      assert(!aliasTy->getDecl()->isGeneric());
       Callback(*this, aliasTy->getDecl());
     } else {
       Type(aliasTy->getSinglyDesugaredType()).walk(*this);

test/PrintAsObjC/Inputs/imported-generic-typealias.h

@@ -0,0 +1,11 @@
+@interface NSObject
+- (void) init;
+@end;
+
+@interface Horse<T> : NSObject
+@end
+
+@interface Barn : NSObject
+@end
+
+typedef int Hay __attribute__((swift_name("Horse.Hay")));

test/PrintAsObjC/imported-generic-typealias.swift

@@ -0,0 +1,14 @@
+// REQUIRES: objc_interop
+
+// RUN: %empty-directory(%t)
+// RUN: %target-swift-frontend(mock-sdk: -sdk %S/../Inputs/clang-importer-sdk -I %t) -parse-as-library %s -typecheck -emit-objc-header-path %t/imported-generic-typealias.h -import-objc-header %S/Inputs/imported-generic-typealias.h -disable-objc-attr-requires-foundation-module
+// RUN: %FileCheck -check-prefix=CHECK -check-prefix=CHECK-PUBLIC %s < %t/imported-generic-typealias.h
+
+@objc public class MyRedBarn : Barn {
+  @objc public func feed(_: Horse<NSObject>.Hay) {}
+}
+
+// CHECK-LABEL: SWIFT_CLASS("_TtC4main9MyRedBarn")
+// CHECK-NEXT: @interface MyRedBarn : Barn
+// CHECK-NEXT: - (void)feed:(Hay)_;
+// CHECK-NEXT: @end