diff --git a/clang/include/clang/AST/Type.h b/clang/include/clang/AST/Type.h
index c9238e95210125..ecbbd73e19fb45 100644
--- a/clang/include/clang/AST/Type.h
+++ b/clang/include/clang/AST/Type.h
@@ -5569,7 +5569,7 @@ class ObjCTypeParamType : public Type,
 
 public:
   bool isSugared() const { return true; }
-  QualType desugar() const;
+  QualType desugar() const { return getCanonicalTypeInternal(); }
 
   static bool classof(const Type *T) {
     return T->getTypeClass() == ObjCTypeParam;
diff --git a/clang/lib/AST/Type.cpp b/clang/lib/AST/Type.cpp
index 4d54ea1061edcd..4fed5b410b1724 100644
--- a/clang/lib/AST/Type.cpp
+++ b/clang/lib/AST/Type.cpp
@@ -663,10 +663,6 @@ ObjCTypeParamType::ObjCTypeParamType(const ObjCTypeParamDecl *D,
   initialize(protocols);
 }
 
-QualType ObjCTypeParamType::desugar() const {
-  return getDecl()->getUnderlyingType();
-}
-
 ObjCObjectType::ObjCObjectType(QualType Canonical, QualType Base,
                                ArrayRef<QualType> typeArgs,
                                ArrayRef<ObjCProtocolDecl *> protocols,
diff --git a/clang/test/SemaObjC/parameterized_classes_subst.m b/clang/test/SemaObjC/parameterized_classes_subst.m
index b6d884760d294e..d14a6e9deb4066 100644
--- a/clang/test/SemaObjC/parameterized_classes_subst.m
+++ b/clang/test/SemaObjC/parameterized_classes_subst.m
@@ -467,17 +467,3 @@ - (void)mapUsingBlock:(id (^)(id))block {
 - (void)mapUsingBlock2:(id)block { // expected-warning{{conflicting parameter types in implementation}}
 }
 @end
-
-// --------------------------------------------------------------------------
-// Use a type parameter as a type argument.
-// --------------------------------------------------------------------------
-// Type bounds in a category/extension are omitted. rdar://problem/54329242
-@interface ParameterizedContainer<T : id<NSCopying>>
-- (ParameterizedContainer<T> *)inInterface;
-@end
-@interface ParameterizedContainer<T> (Cat)
-- (ParameterizedContainer<T> *)inCategory;
-@end
-@interface ParameterizedContainer<U> ()
-- (ParameterizedContainer<U> *)inExtension;
-@end