diff --git a/include/clang/AST/Attr.h b/include/clang/AST/Attr.h
index 35f9b33..f8c2aa9 100644
--- a/include/clang/AST/Attr.h
+++ b/include/clang/AST/Attr.h
@@ -49,6 +49,7 @@
     AnalyzerNoReturn, // Clang-specific.
     Annotate,
     AsmLabel, // Represent GCC asm label extension.
+    BaseCheck,
     Blocks,
     CDecl,
     Cleanup,
@@ -63,6 +64,7 @@
     Format,
     FormatArg,
     GNUInline,
+    Hiding,
     IBOutletKind, // Clang-specific.  Use "Kind" suffix to not conflict with
     Malloc,
     NoDebug,
@@ -72,6 +74,7 @@
     NoThrow,
     ObjCException,
     ObjCNSObject,
+    Override,
     CFReturnsRetained,   // Clang/Checker-specific.
     NSReturnsRetained,   // Clang/Checker-specific.
     Overloadable, // Clang-specific
@@ -558,6 +561,11 @@
 DEF_SIMPLE_ATTR(CFReturnsRetained);
 DEF_SIMPLE_ATTR(NSReturnsRetained);
 
+// C++0x member checking attributes.
+DEF_SIMPLE_ATTR(BaseCheck);
+DEF_SIMPLE_ATTR(Hiding);
+DEF_SIMPLE_ATTR(Override);
+
 #undef DEF_SIMPLE_ATTR
 
 }  // end namespace clang
diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index c3b5045..69a22b5 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -551,6 +551,9 @@
   "|class member|exception declaration|template parameter|block literal}0">;
 def err_auto_var_requires_init : Error<
   "declaration of variable %0 with type %1 requires an initializer">;
+  
+// C++0x attributes
+def err_repeat_attribute : Error<"'%0' attribute cannot be repeated">;
 
 // C++0x [[final]]
 def err_final_function_overridden : Error<
@@ -646,12 +649,14 @@
   "%0 attribute only applies to %select{function|union|"
   "variable and function|function or method|parameter|"
   "parameter or Objective-C method |function, method or block|"
-  "virtual method or class|function, method, or parameter}1 types">;
+  "virtual method or class|function, method, or parameter|class|virtual method"
+  "|member}1 types">;
 def err_attribute_wrong_decl_type : Error<
   "%0 attribute only applies to %select{function|union|"
   "variable and function|function or method|parameter|"
   "parameter or Objective-C method |function, method or block|"
-  "virtual method or class|function, method, or parameter}1 types">;
+  "virtual method or class|function, method, or parameter|class|virtual method"
+  "|member}1 types">;
 def warn_gnu_inline_attribute_requires_inline : Warning<
   "'gnu_inline' attribute requires function to be marked 'inline',"
   " attribute ignored">;
diff --git a/include/clang/Parse/AttributeList.h b/include/clang/Parse/AttributeList.h
index e273cad..ecaa6ae 100644
--- a/include/clang/Parse/AttributeList.h
+++ b/include/clang/Parse/AttributeList.h
@@ -59,6 +59,7 @@
     AT_always_inline,
     AT_analyzer_noreturn,
     AT_annotate,
+    AT_base_check,
     AT_blocks,
     AT_carries_dependency,
     AT_cdecl,
@@ -75,6 +76,7 @@
     AT_format,
     AT_format_arg,
     AT_gnu_inline,
+    AT_hiding,
     AT_malloc,
     AT_mode,
     AT_nodebug,
@@ -85,6 +87,7 @@
     AT_nothrow,
     AT_nsobject,
     AT_objc_exception,
+    AT_override,
     AT_cf_returns_retained,   // Clang-specific.
     AT_ns_returns_retained,   // Clang-specific.
     AT_objc_gc,
diff --git a/lib/Frontend/PCHReaderDecl.cpp b/lib/Frontend/PCHReaderDecl.cpp
index 328bb61..03f3b47 100644
--- a/lib/Frontend/PCHReaderDecl.cpp
+++ b/lib/Frontend/PCHReaderDecl.cpp
@@ -441,6 +441,7 @@
     SIMPLE_ATTR(AnalyzerNoReturn);
     STRING_ATTR(Annotate);
     STRING_ATTR(AsmLabel);
+    SIMPLE_ATTR(BaseCheck);
 
     case Attr::Blocks:
       New = ::new (*Context) BlocksAttr(
@@ -485,6 +486,7 @@
     }
 
     SIMPLE_ATTR(GNUInline);
+    SIMPLE_ATTR(Hiding);
 
     case Attr::IBOutletKind:
       New = ::new (*Context) IBOutletAttr();
@@ -518,6 +520,7 @@
     SIMPLE_ATTR(CFReturnsRetained);
     SIMPLE_ATTR(NSReturnsRetained);
     SIMPLE_ATTR(Overloadable);
+    SIMPLE_ATTR(Override);
     SIMPLE_ATTR(Packed);
     UNSIGNED_ATTR(PragmaPack);
     SIMPLE_ATTR(Pure);
diff --git a/lib/Frontend/PCHWriter.cpp b/lib/Frontend/PCHWriter.cpp
index d60af61..06727c4 100644
--- a/lib/Frontend/PCHWriter.cpp
+++ b/lib/Frontend/PCHWriter.cpp
@@ -1764,6 +1764,9 @@
       AddString(cast<AsmLabelAttr>(Attr)->getLabel(), Record);
       break;
 
+    case Attr::BaseCheck:
+      break;
+
     case Attr::Blocks:
       Record.push_back(cast<BlocksAttr>(Attr)->getType()); // FIXME: stable
       break;
@@ -1817,6 +1820,7 @@
     }
 
     case Attr::GNUInline:
+    case Attr::Hiding:
     case Attr::IBOutletKind:
     case Attr::Malloc:
     case Attr::NoDebug:
@@ -1837,6 +1841,7 @@
     case Attr::CFReturnsRetained:
     case Attr::NSReturnsRetained:
     case Attr::Overloadable:
+    case Attr::Override:
       break;
 
     case Attr::PragmaPack:
diff --git a/lib/Parse/AttributeList.cpp b/lib/Parse/AttributeList.cpp
index 7e2935c..df48e3a 100644
--- a/lib/Parse/AttributeList.cpp
+++ b/lib/Parse/AttributeList.cpp
@@ -65,11 +65,12 @@
     .Case("final", AT_final)
     .Case("cdecl", AT_cdecl)
     .Case("const", AT_const)
-    .Case("packed", AT_packed)
-    .Case("malloc", AT_malloc)
-    .Case("format", AT_format)
-    .Case("unused", AT_unused)
     .Case("blocks", AT_blocks)
+    .Case("format", AT_format)
+    .Case("hiding", AT_hiding)
+    .Case("malloc", AT_malloc)
+    .Case("packed", AT_packed)
+    .Case("unused", AT_unused)
     .Case("aligned", AT_aligned)
     .Case("cleanup", AT_cleanup)
     .Case("nodebug", AT_nodebug)
@@ -80,15 +81,17 @@
     .Case("section", AT_section)
     .Case("stdcall", AT_stdcall)
     .Case("annotate", AT_annotate)
-    .Case("noreturn", AT_noreturn)
-    .Case("noinline", AT_noinline)
     .Case("fastcall", AT_fastcall)
     .Case("iboutlet", AT_IBOutlet)
+    .Case("noreturn", AT_noreturn)
+    .Case("noinline", AT_noinline)
+    .Case("override", AT_override)
     .Case("sentinel", AT_sentinel)
     .Case("NSObject", AT_nsobject)
     .Case("dllimport", AT_dllimport)
     .Case("dllexport", AT_dllexport)
     .Case("may_alias", IgnoredAttribute) // FIXME: TBAA
+    .Case("base_check", AT_base_check)
     .Case("deprecated", AT_deprecated)
     .Case("visibility", AT_visibility)
     .Case("destructor", AT_destructor)
diff --git a/lib/Parse/ParseDeclCXX.cpp b/lib/Parse/ParseDeclCXX.cpp
index 2a3b5d6..59cb90d 100644
--- a/lib/Parse/ParseDeclCXX.cpp
+++ b/lib/Parse/ParseDeclCXX.cpp
@@ -1699,9 +1699,12 @@
       switch(AttributeList::getKind(AttrName))
       {
       // No arguments
-      case AttributeList::AT_noreturn:
+      case AttributeList::AT_base_check:
+      case AttributeList::AT_carries_dependency:
       case AttributeList::AT_final:
-      case AttributeList::AT_carries_dependency: {
+      case AttributeList::AT_hiding:
+      case AttributeList::AT_noreturn:
+      case AttributeList::AT_override: {
         if (Tok.is(tok::l_paren)) {
           Diag(Tok.getLocation(), diag::err_cxx0x_attribute_forbids_arguments)
             << AttrName->getName();
diff --git a/lib/Sema/SemaDeclAttr.cpp b/lib/Sema/SemaDeclAttr.cpp
index 2405d52..f40f125 100644
--- a/lib/Sema/SemaDeclAttr.cpp
+++ b/lib/Sema/SemaDeclAttr.cpp
@@ -1825,15 +1825,94 @@
       << Attr.getName() << 7 /*virtual method or class*/;
     return;
   }
-
-  // FIXME: Check that it's not specified more than once in an attribute-
-  //        specifier and that it conforms to the C++0x rules for
-  //        redeclarations.
+  
+  // FIXME: Conform to C++0x redeclaration rules.
+  
+  if (d->getAttr<FinalAttr>()) {
+    S.Diag(Attr.getLoc(), diag::err_repeat_attribute) << "final";
+    return;
+  }
 
   d->addAttr(::new (S.Context) FinalAttr());
 }
 
 //===----------------------------------------------------------------------===//
+// C++0x member checking attributes
+//===----------------------------------------------------------------------===//
+
+static void HandleBaseCheckAttr(Decl *d, const AttributeList &Attr, Sema &S) {
+  if (Attr.getNumArgs() != 0) {
+    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
+    return;
+  }
+  
+  if (!isa<CXXRecordDecl>(d)) {
+    S.Diag(Attr.getLoc(),
+           Attr.isCXX0XAttribute() ? diag::err_attribute_wrong_decl_type
+                                   : diag::warn_attribute_wrong_decl_type)
+      << Attr.getName() << 9 /*class*/;
+    return;
+  }
+  
+  if (d->getAttr<BaseCheckAttr>()) {
+    S.Diag(Attr.getLoc(), diag::err_repeat_attribute) << "base_check";
+    return;
+  }
+  
+  d->addAttr(::new (S.Context) BaseCheckAttr());
+}
+
+static void HandleHidingAttr(Decl *d, const AttributeList &Attr, Sema &S) {
+  if (Attr.getNumArgs() != 0) {
+    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
+    return;
+  }
+
+  if (!isa<RecordDecl>(d->getDeclContext())) {
+    // FIXME: It's not the type that's the problem
+    S.Diag(Attr.getLoc(),
+           Attr.isCXX0XAttribute() ? diag::err_attribute_wrong_decl_type
+                                   : diag::warn_attribute_wrong_decl_type)
+      << Attr.getName() << 11 /*member*/;
+    return;
+  }
+
+  // FIXME: Conform to C++0x redeclaration rules.
+
+  if (d->getAttr<HidingAttr>()) {
+    S.Diag(Attr.getLoc(), diag::err_repeat_attribute) << "hiding";
+    return;
+  }
+
+  d->addAttr(::new (S.Context) HidingAttr());
+}
+
+static void HandleOverrideAttr(Decl *d, const AttributeList &Attr, Sema &S) {
+  if (Attr.getNumArgs() != 0) {
+    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
+    return;
+  }
+
+  if (!isa<CXXMethodDecl>(d) || !cast<CXXMethodDecl>(d)->isVirtual()) {
+    // FIXME: It's not the type that's the problem
+    S.Diag(Attr.getLoc(),
+           Attr.isCXX0XAttribute() ? diag::err_attribute_wrong_decl_type
+                                   : diag::warn_attribute_wrong_decl_type)
+      << Attr.getName() << 10 /*virtual method*/;
+    return;
+  }
+
+  // FIXME: Conform to C++0x redeclaration rules.
+
+  if (d->getAttr<OverrideAttr>()) {
+    S.Diag(Attr.getLoc(), diag::err_repeat_attribute) << "override";
+    return;
+  }
+
+  d->addAttr(::new (S.Context) OverrideAttr());
+}
+
+//===----------------------------------------------------------------------===//
 // Checker-specific attribute handlers.
 //===----------------------------------------------------------------------===//
 
@@ -1894,34 +1973,37 @@
     // Ignore these, these are type attributes, handled by
     // ProcessTypeAttributes.
     break;
-  case AttributeList::AT_alias:       HandleAliasAttr     (D, Attr, S); break;
-  case AttributeList::AT_aligned:     HandleAlignedAttr   (D, Attr, S); break;
+  case AttributeList::AT_alias:       HandleAliasAttr       (D, Attr, S); break;
+  case AttributeList::AT_aligned:     HandleAlignedAttr     (D, Attr, S); break;
   case AttributeList::AT_always_inline:
     HandleAlwaysInlineAttr  (D, Attr, S); break;
   case AttributeList::AT_analyzer_noreturn:
     HandleAnalyzerNoReturnAttr  (D, Attr, S); break;
-  case AttributeList::AT_annotate:    HandleAnnotateAttr  (D, Attr, S); break;
+  case AttributeList::AT_annotate:    HandleAnnotateAttr    (D, Attr, S); break;
+  case AttributeList::AT_base_check:  HandleBaseCheckAttr   (D, Attr, S); break;
   case AttributeList::AT_carries_dependency:
-                                      HandleDependencyAttr (D, Attr, S); break;
-  case AttributeList::AT_cdecl:       HandleCDeclAttr     (D, Attr, S); break;
-  case AttributeList::AT_constructor: HandleConstructorAttr(D, Attr, S); break;
-  case AttributeList::AT_deprecated:  HandleDeprecatedAttr(D, Attr, S); break;
-  case AttributeList::AT_destructor:  HandleDestructorAttr(D, Attr, S); break;
-  case AttributeList::AT_dllexport:   HandleDLLExportAttr (D, Attr, S); break;
-  case AttributeList::AT_dllimport:   HandleDLLImportAttr (D, Attr, S); break;
+                                      HandleDependencyAttr  (D, Attr, S); break;
+  case AttributeList::AT_cdecl:       HandleCDeclAttr       (D, Attr, S); break;
+  case AttributeList::AT_constructor: HandleConstructorAttr (D, Attr, S); break;
+  case AttributeList::AT_deprecated:  HandleDeprecatedAttr  (D, Attr, S); break;
+  case AttributeList::AT_destructor:  HandleDestructorAttr  (D, Attr, S); break;
+  case AttributeList::AT_dllexport:   HandleDLLExportAttr   (D, Attr, S); break;
+  case AttributeList::AT_dllimport:   HandleDLLImportAttr   (D, Attr, S); break;
   case AttributeList::AT_ext_vector_type:
     HandleExtVectorTypeAttr(scope, D, Attr, S);
     break;
-  case AttributeList::AT_fastcall:    HandleFastCallAttr  (D, Attr, S); break;
-  case AttributeList::AT_final:       HandleFinalAttr     (D, Attr, S); break;
-  case AttributeList::AT_format:      HandleFormatAttr    (D, Attr, S); break;
-  case AttributeList::AT_format_arg:  HandleFormatArgAttr (D, Attr, S); break;
-  case AttributeList::AT_gnu_inline:  HandleGNUInlineAttr (D, Attr, S); break;
-  case AttributeList::AT_mode:        HandleModeAttr      (D, Attr, S); break;
-  case AttributeList::AT_malloc:      HandleMallocAttr    (D, Attr, S); break;
-  case AttributeList::AT_nonnull:     HandleNonNullAttr   (D, Attr, S); break;
-  case AttributeList::AT_noreturn:    HandleNoReturnAttr  (D, Attr, S); break;
-  case AttributeList::AT_nothrow:     HandleNothrowAttr   (D, Attr, S); break;
+  case AttributeList::AT_fastcall:    HandleFastCallAttr    (D, Attr, S); break;
+  case AttributeList::AT_final:       HandleFinalAttr       (D, Attr, S); break;
+  case AttributeList::AT_format:      HandleFormatAttr      (D, Attr, S); break;
+  case AttributeList::AT_format_arg:  HandleFormatArgAttr   (D, Attr, S); break;
+  case AttributeList::AT_gnu_inline:  HandleGNUInlineAttr   (D, Attr, S); break;
+  case AttributeList::AT_hiding:      HandleHidingAttr      (D, Attr, S); break;
+  case AttributeList::AT_mode:        HandleModeAttr        (D, Attr, S); break;
+  case AttributeList::AT_malloc:      HandleMallocAttr      (D, Attr, S); break;
+  case AttributeList::AT_nonnull:     HandleNonNullAttr     (D, Attr, S); break;
+  case AttributeList::AT_noreturn:    HandleNoReturnAttr    (D, Attr, S); break;
+  case AttributeList::AT_nothrow:     HandleNothrowAttr     (D, Attr, S); break;
+  case AttributeList::AT_override:    HandleOverrideAttr    (D, Attr, S); break;
 
   // Checker-specific.
   case AttributeList::AT_ns_returns_retained:
@@ -1931,18 +2013,18 @@
   case AttributeList::AT_reqd_wg_size:
     HandleReqdWorkGroupSize(D, Attr, S); break;
 
-  case AttributeList::AT_packed:      HandlePackedAttr    (D, Attr, S); break;
-  case AttributeList::AT_section:     HandleSectionAttr   (D, Attr, S); break;
-  case AttributeList::AT_stdcall:     HandleStdCallAttr   (D, Attr, S); break;
-  case AttributeList::AT_unavailable: HandleUnavailableAttr(D, Attr, S); break;
-  case AttributeList::AT_unused:      HandleUnusedAttr    (D, Attr, S); break;
-  case AttributeList::AT_used:        HandleUsedAttr      (D, Attr, S); break;
-  case AttributeList::AT_vector_size: HandleVectorSizeAttr(D, Attr, S); break;
-  case AttributeList::AT_visibility:  HandleVisibilityAttr(D, Attr, S); break;
+  case AttributeList::AT_packed:      HandlePackedAttr      (D, Attr, S); break;
+  case AttributeList::AT_section:     HandleSectionAttr     (D, Attr, S); break;
+  case AttributeList::AT_stdcall:     HandleStdCallAttr     (D, Attr, S); break;
+  case AttributeList::AT_unavailable: HandleUnavailableAttr (D, Attr, S); break;
+  case AttributeList::AT_unused:      HandleUnusedAttr      (D, Attr, S); break;
+  case AttributeList::AT_used:        HandleUsedAttr        (D, Attr, S); break;
+  case AttributeList::AT_vector_size: HandleVectorSizeAttr  (D, Attr, S); break;
+  case AttributeList::AT_visibility:  HandleVisibilityAttr  (D, Attr, S); break;
   case AttributeList::AT_warn_unused_result: HandleWarnUnusedResult(D,Attr,S);
     break;
-  case AttributeList::AT_weak:        HandleWeakAttr      (D, Attr, S); break;
-  case AttributeList::AT_weak_import: HandleWeakImportAttr(D, Attr, S); break;
+  case AttributeList::AT_weak:        HandleWeakAttr        (D, Attr, S); break;
+  case AttributeList::AT_weak_import: HandleWeakImportAttr  (D, Attr, S); break;
   case AttributeList::AT_transparent_union:
     HandleTransparentUnionAttr(D, Attr, S);
     break;
@@ -1950,15 +2032,15 @@
     HandleObjCExceptionAttr(D, Attr, S);
     break;
   case AttributeList::AT_overloadable:HandleOverloadableAttr(D, Attr, S); break;
-  case AttributeList::AT_nsobject:    HandleObjCNSObject  (D, Attr, S); break;
-  case AttributeList::AT_blocks:      HandleBlocksAttr    (D, Attr, S); break;
-  case AttributeList::AT_sentinel:    HandleSentinelAttr  (D, Attr, S); break;
-  case AttributeList::AT_const:       HandleConstAttr     (D, Attr, S); break;
-  case AttributeList::AT_pure:        HandlePureAttr      (D, Attr, S); break;
-  case AttributeList::AT_cleanup:     HandleCleanupAttr   (D, Attr, S); break;
-  case AttributeList::AT_nodebug:     HandleNoDebugAttr   (D, Attr, S); break;
-  case AttributeList::AT_noinline:    HandleNoInlineAttr  (D, Attr, S); break;
-  case AttributeList::AT_regparm:     HandleRegparmAttr   (D, Attr, S); break;
+  case AttributeList::AT_nsobject:    HandleObjCNSObject    (D, Attr, S); break;
+  case AttributeList::AT_blocks:      HandleBlocksAttr      (D, Attr, S); break;
+  case AttributeList::AT_sentinel:    HandleSentinelAttr    (D, Attr, S); break;
+  case AttributeList::AT_const:       HandleConstAttr       (D, Attr, S); break;
+  case AttributeList::AT_pure:        HandlePureAttr        (D, Attr, S); break;
+  case AttributeList::AT_cleanup:     HandleCleanupAttr     (D, Attr, S); break;
+  case AttributeList::AT_nodebug:     HandleNoDebugAttr     (D, Attr, S); break;
+  case AttributeList::AT_noinline:    HandleNoInlineAttr    (D, Attr, S); break;
+  case AttributeList::AT_regparm:     HandleRegparmAttr     (D, Attr, S); break;
   case AttributeList::IgnoredAttribute:
   case AttributeList::AT_no_instrument_function:  // Interacts with -pg.
     // Just ignore
diff --git a/test/SemaCXX/attr-cxx0x.cpp b/test/SemaCXX/attr-cxx0x.cpp
index fed0ad4..da52d33 100644
--- a/test/SemaCXX/attr-cxx0x.cpp
+++ b/test/SemaCXX/attr-cxx0x.cpp
@@ -22,3 +22,15 @@
 static_assert(alignof(align_multiple) == 8, "l's alignment is wrong");
 static_assert(alignof(align_member) == 8, "quuux's alignment is wrong");
 static_assert(sizeof(align_member) == 8, "quuux's size is wrong");
+
+int bc_fail [[base_check]]; // expected-error {{'base_check' attribute only applies to class types}}
+int hiding_fail [[hiding]]; // expected-error {{'hiding' attribute only applies to member types}}
+int override_fail [[override]]; // expected-error {{'override' attribute only applies to virtual method types}}
+
+struct base {
+  virtual void function();
+  virtual void other_function();
+};
+
+struct [[base_check, base_check]] bc : base { // expected-error {{'base_check' attribute cannot be repeated}}
+};
\ No newline at end of file