diff --git a/clang/include/clang/AST/DeclBase.h b/clang/include/clang/AST/DeclBase.h
index 1656240bc4ee..0473d1ca1f75 100644
--- a/clang/include/clang/AST/DeclBase.h
+++ b/clang/include/clang/AST/DeclBase.h
@@ -227,6 +227,12 @@ private:
   /// required.
   unsigned Used : 1;
 
+  /// \brief Whether this declaration was "referenced".
+  /// The difference with 'Used' is whether the reference appears in a
+  /// evaluated context or not, e.g. functions used in uninstantiated templates
+  /// are regarded as "referenced" but not "used".
+  unsigned Referenced : 1;
+
 protected:
   /// Access - Used by C++ decls for the access specifier.
   // NOTE: VC++ treats enums as signed, avoid using the AccessSpecifier enum
@@ -261,7 +267,7 @@ protected:
   Decl(Kind DK, DeclContext *DC, SourceLocation L)
     : NextDeclInContext(0), DeclCtx(DC),
       Loc(L), DeclKind(DK), InvalidDecl(0),
-      HasAttrs(false), Implicit(false), Used(false),
+      HasAttrs(false), Implicit(false), Used(false), Referenced(false),
       Access(AS_none), PCHLevel(0), ChangedAfterLoad(false),
       IdentifierNamespace(getIdentifierNamespaceForKind(DK)),
       HasCachedLinkage(0) 
@@ -271,7 +277,7 @@ protected:
 
   Decl(Kind DK, EmptyShell Empty)
     : NextDeclInContext(0), DeclKind(DK), InvalidDecl(0),
-      HasAttrs(false), Implicit(false), Used(false),
+      HasAttrs(false), Implicit(false), Used(false), Referenced(false),
       Access(AS_none), PCHLevel(0), ChangedAfterLoad(false),
       IdentifierNamespace(getIdentifierNamespaceForKind(DK)),
       HasCachedLinkage(0)
@@ -408,6 +414,11 @@ public:
 
   void setUsed(bool U = true) { Used = U; }
 
+  /// \brief Whether this declaration was referenced.
+  bool isReferenced() const;
+
+  void setReferenced(bool R = true) { Referenced = R; }
+
   /// \brief Determine the availability of the given declaration.
   ///
   /// This routine will determine the most restrictive availability of
diff --git a/clang/include/clang/Basic/DiagnosticGroups.td b/clang/include/clang/Basic/DiagnosticGroups.td
index c8465508c8b6..15f3dbd4640d 100644
--- a/clang/include/clang/Basic/DiagnosticGroups.td
+++ b/clang/include/clang/Basic/DiagnosticGroups.td
@@ -154,6 +154,8 @@ def UnusedLabel : DiagGroup<"unused-label">;
 def UnusedParameter : DiagGroup<"unused-parameter">;
 def UnusedValue    : DiagGroup<"unused-value">;
 def UnusedVariable : DiagGroup<"unused-variable">;
+def UnneededInternalDecl : DiagGroup<"unneeded-internal-declaration">;
+def UnneededMemberFunction : DiagGroup<"unneeded-member-function">;
 def UsedButMarkedUnused : DiagGroup<"used-but-marked-unused">;
 def ReadOnlySetterAttrs : DiagGroup<"readonly-setter-attrs">;
 def Reorder : DiagGroup<"reorder">;
@@ -198,11 +200,16 @@ def Conversion : DiagGroup<"conversion",
                             BoolConversions]>,
                  DiagCategory<"Value Conversion Issue">;
 
+def Unneeded : DiagGroup<"unneeded",
+                         [UnneededInternalDecl
+                       //,UnneededMemberFunction (clean-up llvm before enabling)
+                          ]>;
+
 def Unused : DiagGroup<"unused",
                        [UnusedArgument, UnusedFunction, UnusedLabel,
                         // UnusedParameter, (matches GCC's behavior)
                         // UnusedMemberFunction, (clean-up llvm before enabling)
-                        UnusedValue, UnusedVariable]>,
+                        UnusedValue, UnusedVariable, Unneeded]>,
                         DiagCategory<"Unused Entity Issue">;
 
 // Format settings.
diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
index 3ca45d4cf35f..ce592a3c953d 100644
--- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -116,6 +116,12 @@ def warn_unused_member_function : Warning<"unused member function %0">,
   InGroup<UnusedMemberFunction>, DefaultIgnore;
 def warn_used_but_marked_unused: Warning<"%0 was marked unused but was used">,
   InGroup<UsedButMarkedUnused>, DefaultIgnore;
+def warn_unneeded_internal_decl : Warning<
+  "%select{function|variable}0 %1 is not needed and will not be emitted">,
+  InGroup<UnneededInternalDecl>, DefaultIgnore;
+def warn_unneeded_member_function : Warning<
+  "member function %0 is not needed and will not be emitted">,
+  InGroup<UnneededMemberFunction>, DefaultIgnore;
 
 def warn_parameter_size: Warning<
   "%0 is a large (%1 bytes) pass-by-value argument; "
diff --git a/clang/lib/AST/DeclBase.cpp b/clang/lib/AST/DeclBase.cpp
index 673b718ba0ed..41a036142504 100644
--- a/clang/lib/AST/DeclBase.cpp
+++ b/clang/lib/AST/DeclBase.cpp
@@ -242,6 +242,18 @@ bool Decl::isUsed(bool CheckUsedAttr) const {
   return false; 
 }
 
+bool Decl::isReferenced() const { 
+  if (Referenced)
+    return true;
+
+  // Check redeclarations.
+  for (redecl_iterator I = redecls_begin(), E = redecls_end(); I != E; ++I)
+    if (I->Referenced)
+      return true;
+
+  return false; 
+}
+
 /// \brief Determine the availability of the given declaration based on
 /// the target platform.
 ///
diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index a83722d82452..403cf6246cfe 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -473,16 +473,30 @@ void Sema::ActOnEndOfTranslationUnit() {
           DiagD = FD;
         if (DiagD->isDeleted())
           continue; // Deleted functions are supposed to be unused.
-        Diag(DiagD->getLocation(),
-             isa<CXXMethodDecl>(DiagD) ? diag::warn_unused_member_function
-                                       : diag::warn_unused_function)
-              << DiagD->getDeclName();
+        if (DiagD->isReferenced()) {
+          if (isa<CXXMethodDecl>(DiagD))
+            Diag(DiagD->getLocation(), diag::warn_unneeded_member_function)
+                  << DiagD->getDeclName();
+          else
+            Diag(DiagD->getLocation(), diag::warn_unneeded_internal_decl)
+                  << /*function*/0 << DiagD->getDeclName();
+        } else {
+          Diag(DiagD->getLocation(),
+               isa<CXXMethodDecl>(DiagD) ? diag::warn_unused_member_function
+                                         : diag::warn_unused_function)
+                << DiagD->getDeclName();
+        }
       } else {
         const VarDecl *DiagD = cast<VarDecl>(*I)->getDefinition();
         if (!DiagD)
           DiagD = cast<VarDecl>(*I);
-        Diag(DiagD->getLocation(), diag::warn_unused_variable)
-              << DiagD->getDeclName();
+        if (DiagD->isReferenced()) {
+          Diag(DiagD->getLocation(), diag::warn_unneeded_internal_decl)
+                << /*variable*/1 << DiagD->getDeclName();
+        } else {
+          Diag(DiagD->getLocation(), diag::warn_unused_variable)
+                << DiagD->getDeclName();
+        }
       }
     }
 
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index 9415673a7747..8eb0177046da 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -9885,6 +9885,8 @@ Sema::PopExpressionEvaluationContext() {
 void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) {
   assert(D && "No declaration?");
 
+  D->setReferenced();
+
   if (D->isUsed(false))
     return;
 
diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 3fe5fd5c9528..0ff7ff4d4064 100644
--- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -298,8 +298,10 @@ Decl *TemplateDeclInstantiator::VisitVarDecl(VarDecl *D) {
 
   Var->setAccess(D->getAccess());
   
-  if (!D->isStaticDataMember())
+  if (!D->isStaticDataMember()) {
     Var->setUsed(D->isUsed(false));
+    Var->setReferenced(D->isReferenced());
+  }
   
   // FIXME: In theory, we could have a previous declaration for variables that
   // are not static data members.
diff --git a/clang/lib/Serialization/ASTReaderDecl.cpp b/clang/lib/Serialization/ASTReaderDecl.cpp
index 5b4a64eeb5c9..889ef7324c83 100644
--- a/clang/lib/Serialization/ASTReaderDecl.cpp
+++ b/clang/lib/Serialization/ASTReaderDecl.cpp
@@ -214,6 +214,7 @@ void ASTDeclReader::VisitDecl(Decl *D) {
   }
   D->setImplicit(Record[Idx++]);
   D->setUsed(Record[Idx++]);
+  D->setReferenced(Record[Idx++]);
   D->setAccess((AccessSpecifier)Record[Idx++]);
   D->setPCHLevel(Record[Idx++] + (F.Type <= ASTReader::PCH));
 }
diff --git a/clang/lib/Serialization/ASTWriterDecl.cpp b/clang/lib/Serialization/ASTWriterDecl.cpp
index 1306ffda6dd1..b3b55f584aec 100644
--- a/clang/lib/Serialization/ASTWriterDecl.cpp
+++ b/clang/lib/Serialization/ASTWriterDecl.cpp
@@ -141,6 +141,7 @@ void ASTDeclWriter::VisitDecl(Decl *D) {
     Writer.WriteAttributes(D->getAttrs(), Record);
   Record.push_back(D->isImplicit());
   Record.push_back(D->isUsed(false));
+  Record.push_back(D->isReferenced());
   Record.push_back(D->getAccess());
   Record.push_back(D->getPCHLevel());
 }
@@ -1133,6 +1134,7 @@ void ASTWriter::WriteDeclsBlockAbbrevs() {
   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
+  Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
   Abv->Add(BitCodeAbbrevOp(0));                       // PCH level
 
diff --git a/clang/test/Sema/warn-unused-function.c b/clang/test/Sema/warn-unused-function.c
index 5bbcf18a623d..8f4cdcba881e 100644
--- a/clang/test/Sema/warn-unused-function.c
+++ b/clang/test/Sema/warn-unused-function.c
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -fsyntax-only -Wunused-function -verify %s
+// RUN: %clang_cc1 -fsyntax-only -Wunused-function -Wunneeded-internal-declaration -verify %s
 // RUN: %clang_cc1 -fsyntax-only -verify -Wunused %s
 // RUN: %clang_cc1 -fsyntax-only -verify -Wall %s
 
@@ -6,7 +6,7 @@ void foo() {}
 static void f2() {} 
 static void f1() {f2();} // expected-warning{{unused}}
 
-static int f0() { return 17; } // expected-warning{{unused}}
+static int f0() { return 17; } // expected-warning{{not needed and will not be emitted}}
 int x = sizeof(f0());
 
 static void f3();
@@ -46,7 +46,7 @@ static void f12(void) { }  // expected-warning{{unused}}
 static void f12(void);
 
 // PR7923
-static void unused(void) { unused(); }  // expected-warning{{unused}}
+static void unused(void) { unused(); }  // expected-warning{{not needed and will not be emitted}}
 
 // rdar://8728293
 static void cleanupMalloc(char * const * const allocation) { }
diff --git a/clang/test/SemaCXX/warn-unused-filescoped.cpp b/clang/test/SemaCXX/warn-unused-filescoped.cpp
index c32acb0b48be..dbff4b0e68c1 100644
--- a/clang/test/SemaCXX/warn-unused-filescoped.cpp
+++ b/clang/test/SemaCXX/warn-unused-filescoped.cpp
@@ -78,3 +78,12 @@ namespace test4 {
   void test(A a); // expected-warning {{unused function}}
   extern "C" void test4(A a);
 }
+
+namespace rdar8733476 {
+  static void foo() { } // expected-warning {{not needed and will not be emitted}}
+
+  template <int>
+  void bar() {
+    foo();
+  }
+}