Revert changes outside of ClangTypeImporter

Author: j-hui

lib/ClangImporter/ImportType.cpp

@@ -1653,7 +1653,7 @@ static ImportedType adjustTypeForConcreteImport(
   // optional type.
   bool isIUO = false;
   if (importKind != ImportTypeKind::Typedef && optKind != OTK_None &&
-      canImportAsOptional(hint) && !importedType->isForeignReferenceType()) {
+      canImportAsOptional(hint)) {
     isIUO = optKind == OTK_ImplicitlyUnwrappedOptional;
     importedType = OptionalType::get(importedType);
   }
@@ -2710,8 +2710,7 @@ ParameterList *ClangImporter::Implementation::importFunctionParameterList(
 
     bool knownNonNull = !nonNullArgs.empty() && nonNullArgs[index];
     // Specialized templates need to match the args/result exactly.
-    /*knownNonNull |= clangDecl->isFunctionTemplateSpecialization();*/
-    // FIXME: for CI test, DO NOT MERGE ME
+    knownNonNull |= clangDecl->isFunctionTemplateSpecialization();
 
     // Check nullability of the parameter.
     OptionalTypeKind optionalityOfParam =

test/Interop/Cxx/templates/template-instantiation-irgen.swift

@@ -32,17 +32,17 @@ func takesPtrToStruct(x: UnsafePointer<PlainStruct>) { takesValue(x) }
 func takesPtrToClass(x: UnsafePointer<CxxClass>) { takesValue(x) }
 // CHECK: define {{.*}} void @{{.*}}takesPtrToClass{{.*}}
 
-func takesPtrToFRT(x: UnsafePointer<FRT>) { takesValue(x) }
-// CHECK: define {{.*}} void @{{.*}}takesPtrToFRT{{.*}}
+// TODO: this does not work because this round-trips to UnsafePointer<FRT?>
+// func takesPtrToFRT(x: UnsafePointer<FRT>) { takesValue(x) }
 
 func takesMutPtrToStruct(x: UnsafeMutablePointer<PlainStruct>) { takesValue(x) }
 // CHECK: define {{.*}} void @{{.*}}takesMutPtrToStruct{{.*}}
 
 func takesMutPtrToClass(x: UnsafeMutablePointer<CxxClass>) { takesValue(x) }
 // CHECK: define {{.*}} void @{{.*}}takesMutPtrToClass{{.*}}
 
-func takesMutPtrToFRT(x: UnsafeMutablePointer<FRT>) { takesValue(x) }
-// CHECK: define {{.*}} void @{{.*}}takesMutPtrToFRT{{.*}}
+// TODO: this does not work because this round-trips to UnsafeMutablePointer<FRT?>
+// func takesMutPtrToFRT(x: UnsafeMutablePointer<FRT>) { takesValue(x) }
 
 // TODO: optional pointers are not yet supported but they should be
 // func takesCPtr() { takesValue(intPtr) }