diff --git a/clang/include/clang/AST/ASTNodeTraverser.h b/clang/include/clang/AST/ASTNodeTraverser.h
--- a/clang/include/clang/AST/ASTNodeTraverser.h
+++ b/clang/include/clang/AST/ASTNodeTraverser.h
@@ -384,7 +384,8 @@
   }
   void VisitAttributedType(const AttributedType *T) {
     // FIXME: AttrKind
-    Visit(T->getModifiedType());
+    if (T->getModifiedType() != T->getEquivalentType())
+      Visit(T->getModifiedType());
   }
   void VisitBTFTagAttributedType(const BTFTagAttributedType *T) {
     Visit(T->getWrappedType());
diff --git a/clang/test/AST/ast-dump-attr-type.cpp b/clang/test/AST/ast-dump-attr-type.cpp
new file mode 100644
--- /dev/null
+++ b/clang/test/AST/ast-dump-attr-type.cpp
@@ -0,0 +1,24 @@
+// RUN: %clang_cc1 -triple x86_64-unknown-unknown -fsyntax-only -ast-dump %s | FileCheck %s
+
+int * _Nonnull x;
+using Ty = decltype(x);
+
+// CHECK: TypeAliasDecl 0x{{[^ ]*}}  <line:4:1, col:22> col:7 Ty 'decltype(x)':'int *'
+// CHECK-NEXT:  `-DecltypeType 0x{{[^ ]*}} 'decltype(x)' sugar
+// CHECK-NEXT:     |-DeclRefExpr 0x{{[^ ]*}} <col:21> 'int * _Nonnull':'int *' lvalue Var 0x{{[^ ]*}} 'x' 'int * _Nonnull':'int *' non_odr_use_unevaluated
+// CHECK-NEXT:    `-AttributedType 0x{{[^ ]*}} 'int * _Nonnull' sugar
+// CHECK-NEXT:      `-PointerType 0x{{[^ ]*}} 'int *'
+// CHECK-NEXT:        `-BuiltinType 0x{{[^ ]*}} 'int'
+// CHECK-NOT:       `-PointerType
+
+[[clang::address_space(3)]] int *y;
+using Ty1 = decltype(y);
+
+// CHECK: TypeAliasDecl 0x{{[^ ]*}} <line:15:1, col:23> col:7 Ty1 'decltype(y)':'__attribute__((address_space(3))) int *'
+// CHECK-NEXT: `-DecltypeType 0x{{[^ ]*}} 'decltype(y)' sugar
+// CHECK-NEXT:   |-DeclRefExpr 0x{{[^ ]*}} <col:22> '__attribute__((address_space(3))) int *' lvalue Var 0x{{[^ ]*}} 'y' '__attribute__((address_space(3))) int *' non_odr_use_unevaluated
+// CHECK-NEXT:     `-PointerType 0x{{[^ ]*}} '__attribute__((address_space(3))) int *'
+// CHECK-NEXT:       `-AttributedType 0x{{[^ ]*}} '__attribute__((address_space(3))) int' sugar
+// CHECK-NEXT          |-BuiltinType 0x{{[^ ]*}} 'int'
+// CHECK-NEXT          `-QualType 0x{{[^ ]*}} '__attribute__((address_space(3))) int' __attribute__((address_space(3)))
+// CHECK-NEXT            `-BuiltinType 0x{{[^ ]*}} 'int'
diff --git a/clang/test/AST/ast-dump-types-json.cpp b/clang/test/AST/ast-dump-types-json.cpp
--- a/clang/test/AST/ast-dump-types-json.cpp
+++ b/clang/test/AST/ast-dump-types-json.cpp
@@ -203,32 +203,6 @@
 // CHECK-NEXT:            ]
 // CHECK-NEXT:           }
 // CHECK-NEXT:          ]
-// CHECK-NEXT:         },
-// CHECK-NEXT:         {
-// CHECK-NEXT:          "id": "0x{{.*}}",
-// CHECK-NEXT:          "kind": "ParenType",
-// CHECK-NEXT:          "type": {
-// CHECK-NEXT:           "qualType": "void ()"
-// CHECK-NEXT:          },
-// CHECK-NEXT:          "inner": [
-// CHECK-NEXT:           {
-// CHECK-NEXT:            "id": "0x{{.*}}",
-// CHECK-NEXT:            "kind": "FunctionProtoType",
-// CHECK-NEXT:            "type": {
-// CHECK-NEXT:             "qualType": "void ()"
-// CHECK-NEXT:            },
-// CHECK-NEXT:            "cc": "cdecl",
-// CHECK-NEXT:            "inner": [
-// CHECK-NEXT:             {
-// CHECK-NEXT:              "id": "0x{{.*}}",
-// CHECK-NEXT:              "kind": "BuiltinType",
-// CHECK-NEXT:              "type": {
-// CHECK-NEXT:               "qualType": "void"
-// CHECK-NEXT:              }
-// CHECK-NEXT:             }
-// CHECK-NEXT:            ]
-// CHECK-NEXT:           }
-// CHECK-NEXT:          ]
 // CHECK-NEXT:         }
 // CHECK-NEXT:        ]
 // CHECK-NEXT:       }