Index: include/clang/Basic/Attr.td
===================================================================
--- include/clang/Basic/Attr.td
+++ include/clang/Basic/Attr.td
@@ -887,8 +887,8 @@
 
 def Mode : Attr {
   let Spellings = [GCC<"mode">];
-  let Subjects = SubjectList<[Var, TypedefName], ErrorDiag,
-                             "ExpectedVariableOrTypedef">;
+  let Subjects = SubjectList<[Var, TypedefName, Field], ErrorDiag,
+                             "ExpectedVariableFieldOrTypedef">;
   let Args = [IdentifierArgument<"Mode">];
   let Documentation = [Undocumented];
 }
Index: include/clang/Basic/DiagnosticSemaKinds.td
===================================================================
--- include/clang/Basic/DiagnosticSemaKinds.td
+++ include/clang/Basic/DiagnosticSemaKinds.td
@@ -2442,7 +2442,8 @@
   "variables, functions and classes|Objective-C protocols|"
   "functions and global variables|structs, unions, and typedefs|structs and typedefs|"
   "interface or protocol declarations|kernel functions|non-K&R-style functions|"
-  "structs, classes, variables, functions, methods and inline namespaces}1">,
+  "structs, classes, variables, functions, methods and inline namespaces|"
+  "variables, fields and typedefs}1">,
   InGroup<IgnoredAttributes>;
 def err_attribute_wrong_decl_type : Error<warn_attribute_wrong_decl_type.Text>;
 def warn_type_attribute_wrong_type : Warning<
Index: include/clang/Sema/AttributeList.h
===================================================================
--- include/clang/Sema/AttributeList.h
+++ include/clang/Sema/AttributeList.h
@@ -856,7 +856,8 @@
   ExpectedObjectiveCInterfaceOrProtocol,
   ExpectedKernelFunction,
   ExpectedFunctionWithProtoType,
-  ExpectedStructClassVariableFunctionMethodOrInlineNamespace
+  ExpectedStructClassVariableFunctionMethodOrInlineNamespace,
+  ExpectedVariableFieldOrTypedef
 };
 
 }  // end namespace clang
Index: lib/Sema/SemaDeclAttr.cpp
===================================================================
--- lib/Sema/SemaDeclAttr.cpp
+++ lib/Sema/SemaDeclAttr.cpp
@@ -3392,7 +3392,7 @@
   if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(D))
     OldTy = TD->getUnderlyingType();
   else
-    OldTy = cast<VarDecl>(D)->getType();
+    OldTy = cast<ValueDecl>(D)->getType();
 
   // Base type can also be a vector type (see PR17453).
   // Distinguish between base type and base element type.
@@ -3465,7 +3465,7 @@
   if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(D))
     TD->setModedTypeSourceInfo(TD->getTypeSourceInfo(), NewTy);
   else
-    cast<VarDecl>(D)->setType(NewTy);
+    cast<ValueDecl>(D)->setType(NewTy);
 
   D->addAttr(::new (S.Context)
              ModeAttr(Attr.getRange(), S.Context, Name,
Index: test/Sema/attr-mode.c
===================================================================
--- test/Sema/attr-mode.c
+++ test/Sema/attr-mode.c
@@ -24,8 +24,8 @@
 
 int **__attribute((mode(QI)))* i32;  // expected-error{{mode attribute}}
 
-__attribute__((mode(QI))) int invalid_func() { return 1; } // expected-error{{'mode' attribute only applies to variables and typedefs}}
-enum invalid_enum { A1 __attribute__((mode(QI))) }; // expected-error{{'mode' attribute only applies to variables and typedefs}}
+__attribute__((mode(QI))) int invalid_func() { return 1; } // expected-error{{'mode' attribute only applies to variables, fields and typedefs}}
+enum invalid_enum { A1 __attribute__((mode(QI))) }; // expected-error{{'mode' attribute only applies to variables, fields and typedefs}}
 
 typedef _Complex double c32 __attribute((mode(SC)));
 int c32_test[sizeof(c32) == 8 ? 1 : -1];
@@ -76,3 +76,7 @@
 #else
 #error Unknown test architecture.
 #endif
+
+struct S {
+  int n __attribute((mode(HI)));
+};