diff --git a/include/clang/AST/Mangle.h b/include/clang/AST/Mangle.h
index 98e03f5decea229d9491ddcc54ed817af699037d..c13cd257d9bcdf2f54e28548f526b4870b44c40a 100644
--- a/include/clang/AST/Mangle.h
+++ b/include/clang/AST/Mangle.h
@@ -135,9 +135,6 @@ public:
                        const BlockDecl *BD, raw_ostream &Out);
   void mangleBlock(const DeclContext *DC, const BlockDecl *BD,
                    raw_ostream &Out);
-  // Do the right thing.
-  void mangleBlock(const BlockDecl *BD, raw_ostream &Out,
-                   const NamedDecl *ID=0);
 
   void mangleObjCMethodName(const ObjCMethodDecl *MD,
                             raw_ostream &);
diff --git a/lib/AST/Mangle.cpp b/lib/AST/Mangle.cpp
index eb794124490aeedd4c2cf72f0d27f3b3770bb9d5..07c84b2eb4c7459f77a9a475b496c0d3661a83e2 100644
--- a/lib/AST/Mangle.cpp
+++ b/lib/AST/Mangle.cpp
@@ -34,8 +34,6 @@ using namespace clang;
 // FIXME: For blocks we currently mimic GCC's mangling scheme, which leaves
 // much to be desired. Come up with a better mangling scheme.
 
-namespace {
-
 static void mangleFunctionBlock(MangleContext &Context,
                                 StringRef Outer,
                                 const BlockDecl *BD,
@@ -47,22 +45,6 @@ static void mangleFunctionBlock(MangleContext &Context,
     Out << "__" << Outer << "_block_invoke_" << discriminator+1; 
 }
 
-static void checkMangleDC(const DeclContext *DC, const BlockDecl *BD) {
-#ifndef NDEBUG
-  const DeclContext *ExpectedDC = BD->getDeclContext();
-  while (isa<BlockDecl>(ExpectedDC) || isa<EnumDecl>(ExpectedDC))
-    ExpectedDC = ExpectedDC->getParent();
-  // In-class initializers for non-static data members are lexically defined
-  // within the class, but are mangled as if they were specified as constructor
-  // member initializers.
-  if (isa<CXXRecordDecl>(ExpectedDC) && DC != ExpectedDC)
-    DC = DC->getParent();
-  assert(DC == ExpectedDC && "Given decl context did not match expected!");
-#endif
-}
-
-}
-
 void MangleContext::anchor() { }
 
 void MangleContext::mangleGlobalBlock(const BlockDecl *BD,
@@ -85,7 +67,6 @@ void MangleContext::mangleGlobalBlock(const BlockDecl *BD,
 void MangleContext::mangleCtorBlock(const CXXConstructorDecl *CD,
                                     CXXCtorType CT, const BlockDecl *BD,
                                     raw_ostream &ResStream) {
-  checkMangleDC(CD, BD);
   SmallString<64> Buffer;
   llvm::raw_svector_ostream Out(Buffer);
   mangleCXXCtor(CD, CT, Out);
@@ -96,7 +77,6 @@ void MangleContext::mangleCtorBlock(const CXXConstructorDecl *CD,
 void MangleContext::mangleDtorBlock(const CXXDestructorDecl *DD,
                                     CXXDtorType DT, const BlockDecl *BD,
                                     raw_ostream &ResStream) {
-  checkMangleDC(DD, BD);
   SmallString<64> Buffer;
   llvm::raw_svector_ostream Out(Buffer);
   mangleCXXDtor(DD, DT, Out);
@@ -107,7 +87,6 @@ void MangleContext::mangleDtorBlock(const CXXDestructorDecl *DD,
 void MangleContext::mangleBlock(const DeclContext *DC, const BlockDecl *BD,
                                 raw_ostream &Out) {
   assert(!isa<CXXConstructorDecl>(DC) && !isa<CXXDestructorDecl>(DC));
-  checkMangleDC(DC, BD);
 
   SmallString<64> Buffer;
   llvm::raw_svector_ostream Stream(Buffer);
@@ -145,15 +124,3 @@ void MangleContext::mangleObjCMethodName(const ObjCMethodDecl *MD,
   
   Out << OS.str().size() << OS.str();
 }
-
-void MangleContext::mangleBlock(const BlockDecl *BD,
-                                raw_ostream &Out,
-                                const NamedDecl *ID) {
-  const DeclContext *DC = BD->getDeclContext();
-  while (isa<BlockDecl>(DC) || isa<EnumDecl>(DC))
-    DC = DC->getParent();
-  if (DC->isFunctionOrMethod())
-    mangleBlock(DC, BD, Out);
-  else
-    mangleGlobalBlock(BD, ID, Out);
-}
diff --git a/lib/AST/MicrosoftMangle.cpp b/lib/AST/MicrosoftMangle.cpp
index 8c02b3310dbaa6dd2f0574fa5887572147d5d2af..143472f05969d411bd944dbf092515084e5f9889 100644
--- a/lib/AST/MicrosoftMangle.cpp
+++ b/lib/AST/MicrosoftMangle.cpp
@@ -556,7 +556,14 @@ void MicrosoftCXXNameMangler::manglePostfix(const DeclContext *DC,
     return;
 
   if (const BlockDecl *BD = dyn_cast<BlockDecl>(DC)) {
-    Context.mangleBlock(BD, Out);
+    DiagnosticsEngine Diags = Context.getDiags();
+    unsigned DiagID = Diags.getCustomDiagID(DiagnosticsEngine::Error,
+      "cannot mangle a local inside this block yet");
+    Diags.Report(BD->getLocation(), DiagID);
+
+    // FIXME: This is completely, utterly, wrong; see ItaniumMangle
+    // for how this should be done.
+    Out << "__block_invoke" << Context.getBlockId(BD, false);
     Out << '@';
     return manglePostfix(DC->getParent(), NoFunction);
   } else if (isa<CapturedDecl>(DC)) {
diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
index 250442caae63bb9ec0faea66e981498902b81f59..af6a0113f2dccff6bc605251b320668f0a67783e 100644
--- a/lib/CodeGen/CodeGenModule.cpp
+++ b/lib/CodeGen/CodeGenModule.cpp
@@ -434,9 +434,6 @@ StringRef CodeGenModule::getMangledName(GlobalDecl GD) {
     getCXXABI().getMangleContext().mangleCXXCtor(D, GD.getCtorType(), Out);
   else if (const CXXDestructorDecl *D = dyn_cast<CXXDestructorDecl>(ND))
     getCXXABI().getMangleContext().mangleCXXDtor(D, GD.getDtorType(), Out);
-  else if (const BlockDecl *BD = dyn_cast<BlockDecl>(ND))
-    getCXXABI().getMangleContext().mangleBlock(BD, Out,
-      dyn_cast_or_null<VarDecl>(initializedGlobalDecl.getDecl()));
   else
     getCXXABI().getMangleContext().mangleName(ND, Out);