diff --git a/include/clang/AST/ASTDiagnostic.h b/include/clang/AST/ASTDiagnostic.h
index 244ca9e..e9f1505 100644
--- a/include/clang/AST/ASTDiagnostic.h
+++ b/include/clang/AST/ASTDiagnostic.h
@@ -15,7 +15,7 @@
 namespace clang {
   namespace diag { 
     enum {
-#define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP) ENUM,
+#define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP,SFINAE) ENUM,
 #define ASTSTART
 #include "clang/Basic/DiagnosticASTKinds.inc"
 #undef DIAG
diff --git a/include/clang/Analysis/AnalysisDiagnostic.h b/include/clang/Analysis/AnalysisDiagnostic.h
index e82dc9e..3ee7335 100644
--- a/include/clang/Analysis/AnalysisDiagnostic.h
+++ b/include/clang/Analysis/AnalysisDiagnostic.h
@@ -15,7 +15,7 @@
 namespace clang {
   namespace diag { 
     enum {
-#define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP) ENUM,
+#define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP,SFINAE) ENUM,
 #define ANALYSISSTART
 #include "clang/Basic/DiagnosticAnalysisKinds.inc"
 #undef DIAG
diff --git a/include/clang/Basic/Diagnostic.h b/include/clang/Basic/Diagnostic.h
index 22e7fb3..207710b 100644
--- a/include/clang/Basic/Diagnostic.h
+++ b/include/clang/Basic/Diagnostic.h
@@ -50,7 +50,7 @@
 
     // Get typedefs for common diagnostics.
     enum {
-#define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP) ENUM,
+#define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP,SFINAE) ENUM,
 #include "clang/Basic/DiagnosticCommonKinds.inc"
       NUM_BUILTIN_COMMON_DIAGNOSTICS
 #undef DIAG
@@ -313,6 +313,16 @@
   /// the diagnostic, this returns null.
   static const char *getWarningOptionForDiag(unsigned DiagID);
 
+  /// \brief Determines whether the given built-in diagnostic ID is
+  /// for an error that is suppressed if it occurs during C++ template
+  /// argument deduction.
+  ///
+  /// When an error is suppressed due to SFINAE, the template argument
+  /// deduction fails but no diagnostic is emitted. Certain classes of
+  /// errors, such as those errors that involve C++ access control,
+  /// are not SFINAE errors.
+  static bool isBuiltinSFINAEDiag(unsigned DiagID);
+
   /// getDiagnosticLevel - Based on the way the client configured the Diagnostic
   /// object, classify the specified diagnostic ID into a Level, consumable by
   /// the DiagnosticClient.
@@ -409,7 +419,10 @@
 
   /// ProcessDiag - This is the method used to report a diagnostic that is
   /// finally fully formed.
-  void ProcessDiag();
+  ///
+  /// \returns true if the diagnostic was emitted, false if it was
+  /// suppressed.
+  bool ProcessDiag();
 };
 
 //===----------------------------------------------------------------------===//
@@ -448,14 +461,26 @@
     NumCodeModificationHints = D.NumCodeModificationHints;
   }
 
+  /// \brief Simple enumeration value used to give a name to the
+  /// suppress-diagnostic constructor.
+  enum SuppressKind { Suppress };
+
+  /// \brief Create an empty DiagnosticBuilder object that represents
+  /// no actual diagnostic.
+  explicit DiagnosticBuilder(SuppressKind) 
+    : DiagObj(0), NumArgs(0), NumRanges(0), NumCodeModificationHints(0) { }
+
   /// \brief Force the diagnostic builder to emit the diagnostic now.
   ///
   /// Once this function has been called, the DiagnosticBuilder object
   /// should not be used again before it is destroyed.
-  void Emit() {
+  ///
+  /// \returns true if a diagnostic was emitted, false if the
+  /// diagnostic was suppressed.
+  bool Emit() {
     // If DiagObj is null, then its soul was stolen by the copy ctor
     // or the user called Emit().
-    if (DiagObj == 0) return;
+    if (DiagObj == 0) return false;
 
     // When emitting diagnostics, we set the final argument count into
     // the Diagnostic object.
@@ -465,13 +490,15 @@
 
     // Process the diagnostic, sending the accumulated information to the
     // DiagnosticClient.
-    DiagObj->ProcessDiag();
+    bool Emitted = DiagObj->ProcessDiag();
 
     // Clear out the current diagnostic object.
     DiagObj->Clear();
 
     // This diagnostic is dead.
     DiagObj = 0;
+
+    return Emitted;
   }
 
   /// Destructor - The dtor emits the diagnostic if it hasn't already
@@ -486,28 +513,34 @@
   void AddString(const std::string &S) const {
     assert(NumArgs < Diagnostic::MaxArguments &&
            "Too many arguments to diagnostic!");
-    DiagObj->DiagArgumentsKind[NumArgs] = Diagnostic::ak_std_string;
-    DiagObj->DiagArgumentsStr[NumArgs++] = S;
+    if (DiagObj) {
+      DiagObj->DiagArgumentsKind[NumArgs] = Diagnostic::ak_std_string;
+      DiagObj->DiagArgumentsStr[NumArgs++] = S;
+    }
   }
   
   void AddTaggedVal(intptr_t V, Diagnostic::ArgumentKind Kind) const {
     assert(NumArgs < Diagnostic::MaxArguments &&
            "Too many arguments to diagnostic!");
-    DiagObj->DiagArgumentsKind[NumArgs] = Kind;
-    DiagObj->DiagArgumentsVal[NumArgs++] = V;
+    if (DiagObj) {
+      DiagObj->DiagArgumentsKind[NumArgs] = Kind;
+      DiagObj->DiagArgumentsVal[NumArgs++] = V;
+    }
   }
   
   void AddSourceRange(const SourceRange &R) const {
     assert(NumRanges < 
            sizeof(DiagObj->DiagRanges)/sizeof(DiagObj->DiagRanges[0]) &&
            "Too many arguments to diagnostic!");
-    DiagObj->DiagRanges[NumRanges++] = &R;
+    if (DiagObj)
+      DiagObj->DiagRanges[NumRanges++] = &R;
   }    
 
   void AddCodeModificationHint(const CodeModificationHint &Hint) const {
     assert(NumCodeModificationHints < Diagnostic::MaxCodeModificationHints &&
            "Too many code modification hints!");
-    DiagObj->CodeModificationHints[NumCodeModificationHints++] = Hint;
+    if (DiagObj)
+      DiagObj->CodeModificationHints[NumCodeModificationHints++] = Hint;
   }
 };
 
diff --git a/include/clang/Basic/Diagnostic.td b/include/clang/Basic/Diagnostic.td
index 67d8eaa..6aa3b43 100644
--- a/include/clang/Basic/Diagnostic.td
+++ b/include/clang/Basic/Diagnostic.td
@@ -45,6 +45,7 @@
   string      Component = ?;
   string      Text = text;
   DiagClass   Class = DC;
+  bit         SFINAE = 1;
   DiagMapping DefaultMapping = defaultmapping;
   DiagGroup   Group;
 }
@@ -61,6 +62,8 @@
 class DefaultError  { DiagMapping DefaultMapping = MAP_ERROR; }
 class DefaultFatal  { DiagMapping DefaultMapping = MAP_FATAL; }
 
+class NoSFINAE { bit SFINAE = 0; }
+
 // Definitions for Diagnostics.
 include "DiagnosticASTKinds.td"
 include "DiagnosticAnalysisKinds.td"
diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index 26c5fc8..fa4f430 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -331,7 +331,7 @@
 def err_covariant_return_inaccessible_base : Error<
   "return type of virtual function %2 is not covariant with the return type "
   "of the function it overrides "
-  "(conversion from %0 to inaccessible base class %1)">;
+  "(conversion from %0 to inaccessible base class %1)">, NoSFINAE;
 def err_covariant_return_ambiguous_derived_to_base_conv : Error<
   "return type of virtual function %3 is not covariant with the return type of "
   "the function it overrides (ambiguous conversion from derived class "
@@ -782,7 +782,8 @@
 
 // C++ Template Instantiation
 def err_template_recursion_depth_exceeded : Error<
-  "recursive template instantiation exceeded maximum depth of %0">,DefaultFatal;
+  "recursive template instantiation exceeded maximum depth of %0">,
+  DefaultFatal, NoSFINAE;
 def note_template_recursion_depth : Note<
   "use -ftemplate-depth-N to increase recursive template instantiation depth">;
 
@@ -1604,7 +1605,7 @@
 
 // C++ access control
 def err_conv_to_inaccessible_base : Error<
-  "conversion from %0 to inaccessible base class %1">;
+  "conversion from %0 to inaccessible base class %1">, NoSFINAE;
 def note_inheritance_specifier_here : Note<
   "'%0' inheritance specifier here">;
 def note_inheritance_implicitly_private_here : Note<
@@ -1851,8 +1852,10 @@
   "local declaration of %0 hides instance variable">;
 def error_ivar_use_in_class_method : Error<
   "instance variable %0 accessed in class method">;
-def error_private_ivar_access : Error<"instance variable %0 is private">;
-def error_protected_ivar_access : Error<"instance variable %0 is protected">;
+def error_private_ivar_access : Error<"instance variable %0 is private">,
+    NoSFINAE;
+def error_protected_ivar_access : Error<"instance variable %0 is protected">,
+    NoSFINAE;
 def warn_maynot_respond : Warning<"%0  may not respond to %1">;
 def warn_attribute_method_def : Warning<
   "method attribute can only be specified on method declarations">;
diff --git a/include/clang/Driver/DriverDiagnostic.h b/include/clang/Driver/DriverDiagnostic.h
index 2a4413c..705c342 100644
--- a/include/clang/Driver/DriverDiagnostic.h
+++ b/include/clang/Driver/DriverDiagnostic.h
@@ -15,7 +15,7 @@
 namespace clang {
   namespace diag { 
     enum {
-#define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP) ENUM,
+#define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP,SFINAE) ENUM,
 #define DRIVERSTART
 #include "clang/Basic/DiagnosticDriverKinds.inc"
 #undef DIAG
diff --git a/include/clang/Frontend/FrontendDiagnostic.h b/include/clang/Frontend/FrontendDiagnostic.h
index 02432ca..079abae 100644
--- a/include/clang/Frontend/FrontendDiagnostic.h
+++ b/include/clang/Frontend/FrontendDiagnostic.h
@@ -15,7 +15,7 @@
 namespace clang {
   namespace diag { 
     enum {
-#define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP) ENUM,
+#define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP,SFINAE) ENUM,
 #define FRONTENDSTART
 #include "clang/Basic/DiagnosticFrontendKinds.inc"
 #undef DIAG
diff --git a/include/clang/Lex/LexDiagnostic.h b/include/clang/Lex/LexDiagnostic.h
index 1502efb..03d9b7b 100644
--- a/include/clang/Lex/LexDiagnostic.h
+++ b/include/clang/Lex/LexDiagnostic.h
@@ -15,7 +15,7 @@
 namespace clang {
   namespace diag { 
     enum {
-#define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP) ENUM,
+#define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP,SFINAE) ENUM,
 #define LEXSTART
 #include "clang/Basic/DiagnosticLexKinds.inc"
 #undef DIAG
diff --git a/include/clang/Parse/ParseDiagnostic.h b/include/clang/Parse/ParseDiagnostic.h
index a85c6ad..fa600dd 100644
--- a/include/clang/Parse/ParseDiagnostic.h
+++ b/include/clang/Parse/ParseDiagnostic.h
@@ -15,7 +15,7 @@
 namespace clang {
   namespace diag { 
     enum {
-#define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP) ENUM,
+#define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP,SFINAE) ENUM,
 #define PARSESTART
 #include "clang/Basic/DiagnosticParseKinds.inc"
 #undef DIAG
diff --git a/include/clang/Sema/SemaDiagnostic.h b/include/clang/Sema/SemaDiagnostic.h
index e215ed4..de92844 100644
--- a/include/clang/Sema/SemaDiagnostic.h
+++ b/include/clang/Sema/SemaDiagnostic.h
@@ -15,7 +15,7 @@
 namespace clang {
   namespace diag { 
     enum {
-#define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP) ENUM,
+#define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP,SFINAE) ENUM,
 #define SEMASTART
 #include "clang/Basic/DiagnosticSemaKinds.inc"
 #undef DIAG
diff --git a/lib/Basic/Diagnostic.cpp b/lib/Basic/Diagnostic.cpp
index 3b3d61b..323f7a7 100644
--- a/lib/Basic/Diagnostic.cpp
+++ b/lib/Basic/Diagnostic.cpp
@@ -46,6 +46,7 @@
   unsigned short DiagID;
   unsigned Mapping : 3;
   unsigned Class : 3;
+  bool SFINAE : 1;
   const char *Description;
   const char *OptionGroup;
   
@@ -58,8 +59,8 @@
 };
 
 static const StaticDiagInfoRec StaticDiagInfo[] = {
-#define DIAG(ENUM,CLASS,DEFAULT_MAPPING,DESC,GROUP) \
-  { diag::ENUM, DEFAULT_MAPPING, CLASS, DESC, GROUP },
+#define DIAG(ENUM,CLASS,DEFAULT_MAPPING,DESC,GROUP,SFINAE)    \
+  { diag::ENUM, DEFAULT_MAPPING, CLASS, SFINAE, DESC, GROUP },
 #include "clang/Basic/DiagnosticCommonKinds.inc"
 #include "clang/Basic/DiagnosticDriverKinds.inc"
 #include "clang/Basic/DiagnosticFrontendKinds.inc"
@@ -68,7 +69,7 @@
 #include "clang/Basic/DiagnosticASTKinds.inc"
 #include "clang/Basic/DiagnosticSemaKinds.inc"
 #include "clang/Basic/DiagnosticAnalysisKinds.inc"
-{ 0, 0, 0, 0, 0 }
+  { 0, 0, 0, 0, 0, 0}
 };
 #undef DIAG
 
@@ -89,7 +90,7 @@
 #endif
   
   // Search the diagnostic table with a binary search.
-  StaticDiagInfoRec Find = { DiagID, 0, 0, 0, 0 };
+  StaticDiagInfoRec Find = { DiagID, 0, 0, 0, 0, 0 };
   
   const StaticDiagInfoRec *Found =
     std::lower_bound(StaticDiagInfo, StaticDiagInfo + NumDiagEntries, Find);
@@ -115,6 +116,12 @@
   return 0;
 }
 
+bool Diagnostic::isBuiltinSFINAEDiag(unsigned DiagID) {
+  if (const StaticDiagInfoRec *Info = GetDiagInfo(DiagID))
+    return Info->SFINAE && Info->Class != CLASS_NOTE;
+  return false;
+}
+
 /// getDiagClass - Return the class field of the diagnostic.
 ///
 static unsigned getBuiltinDiagClass(unsigned DiagID) {
@@ -399,7 +406,7 @@
 
 /// ProcessDiag - This is the method used to report a diagnostic that is
 /// finally fully formed.
-void Diagnostic::ProcessDiag() {
+bool Diagnostic::ProcessDiag() {
   DiagnosticInfo Info(this);
     
   // Figure out the diagnostic level of this message.
@@ -449,13 +456,13 @@
   // If a fatal error has already been emitted, silence all subsequent
   // diagnostics.
   if (FatalErrorOccurred)
-    return;
+    return false;
 
   // If the client doesn't care about this message, don't issue it.  If this is
   // a note and the last real diagnostic was ignored, ignore it too.
   if (DiagLevel == Diagnostic::Ignored ||
       (DiagLevel == Diagnostic::Note && LastDiagLevel == Diagnostic::Ignored))
-    return;
+    return false;
 
   // If this diagnostic is in a system header and is not a clang error, suppress
   // it.
@@ -464,7 +471,7 @@
       Info.getLocation().getSpellingLoc().isInSystemHeader() &&
       (DiagLevel != Diagnostic::Note || LastDiagLevel == Diagnostic::Ignored)) {
     LastDiagLevel = Diagnostic::Ignored;
-    return;
+    return false;
   }
 
   if (DiagLevel >= Diagnostic::Error) {
@@ -477,6 +484,8 @@
   if (Client->IncludeInDiagnosticCounts()) ++NumDiagnostics;
 
   CurDiagID = ~0U;
+
+  return true;
 }
 
 
diff --git a/lib/Sema/Sema.cpp b/lib/Sema/Sema.cpp
index e3cea5b..4dc5222 100644
--- a/lib/Sema/Sema.cpp
+++ b/lib/Sema/Sema.cpp
@@ -316,7 +316,8 @@
 }
 
 Sema::SemaDiagnosticBuilder::~SemaDiagnosticBuilder() {
-  this->Emit();
+  if (!this->Emit())
+    return;
   
   // If this is not a note, and we're in a template instantiation
   // that is different from the last template instantiation where
diff --git a/lib/Sema/Sema.h b/lib/Sema/Sema.h
index 169ce82..b310568 100644
--- a/lib/Sema/Sema.h
+++ b/lib/Sema/Sema.h
@@ -297,11 +297,21 @@
     SemaDiagnosticBuilder(DiagnosticBuilder &DB, Sema &SemaRef, unsigned DiagID)
       : DiagnosticBuilder(DB), SemaRef(SemaRef), DiagID(DiagID) { }
 
+    explicit SemaDiagnosticBuilder(Sema &SemaRef) 
+      : DiagnosticBuilder(DiagnosticBuilder::Suppress), SemaRef(SemaRef) { }
+
     ~SemaDiagnosticBuilder();
   };
 
   /// \brief Emit a diagnostic.
   SemaDiagnosticBuilder Diag(SourceLocation Loc, unsigned DiagID) {
+    if (isSFINAEContext() && Diagnostic::isBuiltinSFINAEDiag(DiagID)) {
+      // If we encountered an error during template argument
+      // deduction, and that error is one of the SFINAE errors,
+      // supress the diagnostic.
+      return SemaDiagnosticBuilder(*this);
+    }
+
     DiagnosticBuilder DB = Diags.Report(FullSourceLoc(Loc, SourceMgr), DiagID);
     return SemaDiagnosticBuilder(DB, *this, DiagID);
   }
@@ -2322,6 +2332,14 @@
 
   void PrintInstantiationStack();
 
+  /// \brief Determines whether we are currently in a context where
+  /// template argument substitution failures are not considered
+  /// errors.
+  ///
+  /// When this routine returns true, the emission of most diagnostics
+  /// will be suppressed and there will be no local error recovery.
+  bool isSFINAEContext() const;
+
   /// \brief A stack-allocated class that identifies which local
   /// variable declaration instantiations are present in this scope.
   ///
diff --git a/lib/Sema/SemaTemplateInstantiate.cpp b/lib/Sema/SemaTemplateInstantiate.cpp
index 4d03e79..18b2d75 100644
--- a/lib/Sema/SemaTemplateInstantiate.cpp
+++ b/lib/Sema/SemaTemplateInstantiate.cpp
@@ -199,6 +199,34 @@
   }
 }
 
+bool Sema::isSFINAEContext() const {
+  using llvm::SmallVector;
+  for (SmallVector<ActiveTemplateInstantiation, 16>::const_reverse_iterator
+         Active = ActiveTemplateInstantiations.rbegin(),
+         ActiveEnd = ActiveTemplateInstantiations.rend();
+       Active != ActiveEnd;
+       ++Active) {
+
+    switch(Active->Kind) {
+    case ActiveTemplateInstantiation::PartialSpecDeductionInstantiation:
+      // We're in a template argument deduction context, so SFINAE
+      // applies.
+      return true;
+
+    case ActiveTemplateInstantiation::DefaultTemplateArgumentInstantiation:
+      // A default template argument instantiation may or may not be a
+      // SFINAE context; look further up the stack.
+      break;
+
+    case ActiveTemplateInstantiation::TemplateInstantiation:
+      // This is a template instantiation, so there is no SFINAE.
+      return false;
+    }
+  }
+
+  return false;
+}
+
 //===----------------------------------------------------------------------===/
 // Template Instantiation for Types
 //===----------------------------------------------------------------------===/
diff --git a/test/SemaTemplate/temp_class_spec.cpp b/test/SemaTemplate/temp_class_spec.cpp
index 6fedce7..1a53423 100644
--- a/test/SemaTemplate/temp_class_spec.cpp
+++ b/test/SemaTemplate/temp_class_spec.cpp
@@ -251,9 +251,8 @@
             is_nested_value_type_identity<HasValueType<int> >::value? -1 : 1];
 int is_nested_value_type_identity1[
           is_nested_value_type_identity<HasIdentityValueType>::value? 1 : -1];
-// FIXME: Enable when we have SFINAE support
-//int is_nested_value_type_identity2[
-//                   is_nested_value_type_identity<NoValueType>::value? -1 : 1];
+int is_nested_value_type_identity2[
+                   is_nested_value_type_identity<NoValueType>::value? -1 : 1];
 
 
 // C++ [temp.class.spec]p4:
diff --git a/www/cxx_status.html b/www/cxx_status.html
index f1c3fb9..d5ff8ac 100644
--- a/www/cxx_status.html
+++ b/www/cxx_status.html
@@ -2085,10 +2085,10 @@
 </tr>
 <tr>
   <td>&nbsp;&nbsp;&nbsp;&nbsp;14.8.2 [temp.deduct]</td>
-  <td class="broken" align="center"></td>
-  <td class="broken" align="center"></td>
-  <td class="broken" align="center"></td>
-  <td class="broken" align="center"></td>
+  <td class="na" align="center">N/A</td>
+  <td class="na" align="center">N/A</td>
+  <td class="medium" align="center"></td>
+  <td class="na" align="center">N/A</td>
   <td></td>
 </tr>
 <tr>