diff --git a/clang/include/clang/Basic/DiagnosticGroups.td b/clang/include/clang/Basic/DiagnosticGroups.td
index 1cce51ee311172e5550f8b89b5cabdc961392a05..10affb07d31b220e5cdcc0d77264a0ee8dd906ac 100644
--- a/clang/include/clang/Basic/DiagnosticGroups.td
+++ b/clang/include/clang/Basic/DiagnosticGroups.td
@@ -436,3 +436,8 @@ def ObjCRedundantAPIUse : DiagGroup<"objc-redundant-api-use", [
 def ObjCCocoaAPI : DiagGroup<"objc-cocoa-api", [
     ObjCRedundantAPIUse
   ]>;
+
+def ObjCStringComparison : DiagGroup<"objc-string-compare">;
+def ObjCLiteralComparison : DiagGroup<"objc-literal-compare", [
+    ObjCStringComparison
+  ]>;
diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
index e5eea9d48a1872bb65dd90f146f840c0a14bb8c6..0c5c01a6e188504467d619b74dcbf8e278a529fb 100644
--- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -1611,19 +1611,23 @@ def err_box_literal_collection : Error<
   "%select{string|character|boolean|numeric}0 literal must be prefixed by '@' "
   "in a collection">;
 def warn_objc_literal_comparison : Warning<
-  "direct comparison of %select{a string literal|an array literal|"
-  "a dictionary literal|a numeric literal|a boxed expression|}0 has "
-  "undefined behavior">, InGroup<DiagGroup<"objc-literal-compare">>;
+  "direct comparison of %select{an array literal|a dictionary literal|"
+  "a numeric literal|a boxed expression|}0 has undefined behavior">,
+  InGroup<ObjCLiteralComparison>;
+def warn_objc_string_literal_comparison : Warning<
+  "direct comparison of a string literal has undefined behavior">, 
+  InGroup<ObjCStringComparison>;
 def note_objc_literal_comparison_isequal : Note<
   "use 'isEqual:' instead">;
-def err_attr_tlsmodel_arg : Error<"tls_model must be \"global-dynamic\", "
-  "\"local-dynamic\", \"initial-exec\" or \"local-exec\"">;
 
 let CategoryName = "Cocoa API Issue" in {
 def warn_objc_redundant_literal_use : Warning<
   "using %0 with a literal is redundant">, InGroup<ObjCRedundantLiteralUse>;
 }
 
+def err_attr_tlsmodel_arg : Error<"tls_model must be \"global-dynamic\", "
+  "\"local-dynamic\", \"initial-exec\" or \"local-exec\"">;
+
 def err_only_annotate_after_access_spec : Error<
   "access specifier can only have annotation attributes">;
 
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index 0548cccd1fe2e5688989f96b2c11c2d25f936ae4..fabd673d1b160674847a15f112f679334206d89d 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -6744,19 +6744,28 @@ static void diagnoseObjCLiteralComparison(Sema &S, SourceLocation Loc,
                                           BinaryOperator::Opcode Opc){
   Expr *Literal = (isObjCObjectLiteral(LHS) ? LHS : RHS).get();
 
-  unsigned LiteralKind;
+  // This should be kept in sync with warn_objc_literal_comparison.
+  // LK_String should always be last, since it has its own flag.
+  enum {
+    LK_Array,
+    LK_Dictionary,
+    LK_Numeric,
+    LK_Boxed,
+    LK_String
+  } LiteralKind;
+
   switch (Literal->getStmtClass()) {
   case Stmt::ObjCStringLiteralClass:
     // "string literal"
-    LiteralKind = 0;
+    LiteralKind = LK_String;
     break;
   case Stmt::ObjCArrayLiteralClass:
     // "array literal"
-    LiteralKind = 1;
+    LiteralKind = LK_Array;
     break;
   case Stmt::ObjCDictionaryLiteralClass:
     // "dictionary literal"
-    LiteralKind = 2;
+    LiteralKind = LK_Dictionary;
     break;
   case Stmt::ObjCBoxedExprClass: {
     Expr *Inner = cast<ObjCBoxedExpr>(Literal)->getSubExpr();
@@ -6767,20 +6776,20 @@ static void diagnoseObjCLiteralComparison(Sema &S, SourceLocation Loc,
     case Stmt::ObjCBoolLiteralExprClass:
     case Stmt::CXXBoolLiteralExprClass:
       // "numeric literal"
-      LiteralKind = 3;
+      LiteralKind = LK_Numeric;
       break;
     case Stmt::ImplicitCastExprClass: {
       CastKind CK = cast<CastExpr>(Inner)->getCastKind();
       // Boolean literals can be represented by implicit casts.
       if (CK == CK_IntegralToBoolean || CK == CK_IntegralCast) {
-        LiteralKind = 3;
+        LiteralKind = LK_Numeric;
         break;
       }
       // FALLTHROUGH
     }
     default:
       // "boxed expression"
-      LiteralKind = 4;
+      LiteralKind = LK_Boxed;
       break;
     }
     break;
@@ -6789,8 +6798,12 @@ static void diagnoseObjCLiteralComparison(Sema &S, SourceLocation Loc,
     llvm_unreachable("Unknown Objective-C object literal kind");
   }
 
-  S.Diag(Loc, diag::warn_objc_literal_comparison)
-    << LiteralKind << Literal->getSourceRange();
+  if (LiteralKind == LK_String)
+    S.Diag(Loc, diag::warn_objc_string_literal_comparison)
+      << Literal->getSourceRange();
+  else
+    S.Diag(Loc, diag::warn_objc_literal_comparison)
+      << LiteralKind << Literal->getSourceRange();
 
   if (BinaryOperator::isEqualityOp(Opc) &&
       hasIsEqualMethod(S, LHS.get(), RHS.get())) {
diff --git a/clang/test/SemaObjC/objc-literal-comparison.m b/clang/test/SemaObjC/objc-literal-comparison.m
index b0ca139961a0f985de5348206277bcc5984e386d..ea42a176ef03f8f02fc4de181d131c9854495577 100644
--- a/clang/test/SemaObjC/objc-literal-comparison.m
+++ b/clang/test/SemaObjC/objc-literal-comparison.m
@@ -1,4 +1,6 @@
-// RUN: %clang_cc1 -fsyntax-only -verify %s
+// RUN: %clang_cc1 -fsyntax-only -Wno-everything -Wobjc-literal-compare -verify %s
+
+// (test the warning flag as well)
 
 typedef unsigned char BOOL;
 
@@ -63,3 +65,17 @@ void testComparisonsWithoutFixits() {
   if (@"" >= @"") return; // expected-warning{{direct comparison of a string literal has undefined behavior}}
 }
 
+
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wobjc-string-compare"
+
+void testWarningFlags(id obj) {
+  if (obj == @"") return; // no-warning
+  if (@"" == obj) return; // no-warning
+
+  if (obj == @1) return; // expected-warning{{direct comparison of a numeric literal has undefined behavior}} expected-note{{use 'isEqual:' instead}}
+  if (@1 == obj) return; // expected-warning{{direct comparison of a numeric literal has undefined behavior}} expected-note{{use 'isEqual:' instead}}
+}
+
+#pragma clang diagnostic pop
+