diff --git a/include/clang/AST/Decl.h b/include/clang/AST/Decl.h
index cd4535d..214febe 100644
--- a/include/clang/AST/Decl.h
+++ b/include/clang/AST/Decl.h
@@ -1311,20 +1311,29 @@
 
 class TypedefDecl : public TypeDecl {
   /// UnderlyingType - This is the type the typedef is set to.
-  QualType UnderlyingType;
+  DeclaratorInfo *DInfo;
+
   TypedefDecl(DeclContext *DC, SourceLocation L,
-              IdentifierInfo *Id, QualType T)
-    : TypeDecl(Typedef, DC, L, Id), UnderlyingType(T) {}
+              IdentifierInfo *Id, DeclaratorInfo *DInfo)
+    : TypeDecl(Typedef, DC, L, Id), DInfo(DInfo) {}
 
   virtual ~TypedefDecl() {}
 public:
 
   static TypedefDecl *Create(ASTContext &C, DeclContext *DC,
-                             SourceLocation L,IdentifierInfo *Id,
-                             QualType T);
+                             SourceLocation L, IdentifierInfo *Id,
+                             DeclaratorInfo *DInfo);
 
-  QualType getUnderlyingType() const { return UnderlyingType; }
-  void setUnderlyingType(QualType newType) { UnderlyingType = newType; }
+  DeclaratorInfo *getTypeDeclaratorInfo() const {
+    return DInfo;
+  }
+
+  QualType getUnderlyingType() const {
+    return DInfo->getType();
+  }
+  void setTypeDeclaratorInfo(DeclaratorInfo *newType) {
+    DInfo = newType;
+  }
 
   // Implement isa/cast/dyncast/etc.
   static bool classof(const Decl *D) { return D->getKind() == Typedef; }
diff --git a/lib/AST/Decl.cpp b/lib/AST/Decl.cpp
index 19d00de..903d943 100644
--- a/lib/AST/Decl.cpp
+++ b/lib/AST/Decl.cpp
@@ -178,9 +178,9 @@
 }
 
 TypedefDecl *TypedefDecl::Create(ASTContext &C, DeclContext *DC,
-                                 SourceLocation L,
-                                 IdentifierInfo *Id, QualType T) {
-  return new (C) TypedefDecl(DC, L, Id, T);
+                                 SourceLocation L, IdentifierInfo *Id,
+                                 DeclaratorInfo *DInfo) {
+  return new (C) TypedefDecl(DC, L, Id, DInfo);
 }
 
 EnumDecl *EnumDecl::Create(ASTContext &C, DeclContext *DC, SourceLocation L,
diff --git a/lib/Frontend/PCHReaderDecl.cpp b/lib/Frontend/PCHReaderDecl.cpp
index 5925dc6..c3690fb 100644
--- a/lib/Frontend/PCHReaderDecl.cpp
+++ b/lib/Frontend/PCHReaderDecl.cpp
@@ -106,9 +106,9 @@
   // set the underlying type of the typedef *before* we try to read
   // the type associated with the TypedefDecl.
   VisitNamedDecl(TD);
-  TD->setUnderlyingType(Reader.GetType(Record[Idx + 1]));
-  TD->setTypeForDecl(Reader.GetType(Record[Idx]).getTypePtr());
-  Idx += 2;
+  uint64_t TypeData = Record[Idx++];
+  TD->setTypeDeclaratorInfo(Reader.GetDeclaratorInfo(Record, Idx));
+  TD->setTypeForDecl(Reader.GetType(TypeData).getTypePtr());
 }
 
 void PCHDeclReader::VisitTagDecl(TagDecl *TD) {
@@ -612,7 +612,7 @@
     D = Context->getTranslationUnitDecl();
     break;
   case pch::DECL_TYPEDEF:
-    D = TypedefDecl::Create(*Context, 0, SourceLocation(), 0, QualType());
+    D = TypedefDecl::Create(*Context, 0, SourceLocation(), 0, 0);
     break;
   case pch::DECL_ENUM:
     D = EnumDecl::Create(*Context, 0, SourceLocation(), 0, SourceLocation(), 0);
diff --git a/lib/Frontend/PCHWriterDecl.cpp b/lib/Frontend/PCHWriterDecl.cpp
index be940a2..f1853f4 100644
--- a/lib/Frontend/PCHWriterDecl.cpp
+++ b/lib/Frontend/PCHWriterDecl.cpp
@@ -106,7 +106,7 @@
 
 void PCHDeclWriter::VisitTypedefDecl(TypedefDecl *D) {
   VisitTypeDecl(D);
-  Writer.AddTypeRef(D->getUnderlyingType(), Record);
+  Writer.AddDeclaratorInfo(D->getTypeDeclaratorInfo(), Record);
   Code = pch::DECL_TYPEDEF;
 }
 
diff --git a/lib/Frontend/RewriteObjC.cpp b/lib/Frontend/RewriteObjC.cpp
index 0ea0a58..a003262 100644
--- a/lib/Frontend/RewriteObjC.cpp
+++ b/lib/Frontend/RewriteObjC.cpp
@@ -2609,10 +2609,12 @@
 // typedef struct objc_object Protocol;
 QualType RewriteObjC::getProtocolType() {
   if (!ProtocolTypeDecl) {
+    DeclaratorInfo *DInfo
+      = Context->getTrivialDeclaratorInfo(Context->getObjCIdType());
     ProtocolTypeDecl = TypedefDecl::Create(*Context, TUDecl,
                                            SourceLocation(),
                                            &Context->Idents.get("Protocol"),
-                                           Context->getObjCIdType());
+                                           DInfo);
   }
   return Context->getTypeDeclType(ProtocolTypeDecl);
 }
diff --git a/lib/Index/ResolveLocation.cpp b/lib/Index/ResolveLocation.cpp
index 8edd634..4e992f7 100644
--- a/lib/Index/ResolveLocation.cpp
+++ b/lib/Index/ResolveLocation.cpp
@@ -45,6 +45,9 @@
     if (DeclaratorDecl *DD = dyn_cast<DeclaratorDecl>(D))
       if (ContainsLocation(DD->getDeclaratorInfo()))
         return ContainsLoc;
+    if (TypedefDecl *TD = dyn_cast<TypedefDecl>(D))
+      if (ContainsLocation(TD->getTypeDeclaratorInfo()))
+        return ContainsLoc;
 
     return CheckRange(D->getSourceRange());
   }
@@ -109,6 +112,7 @@
   ASTLocation VisitVarDecl(VarDecl *D);
   ASTLocation VisitFunctionDecl(FunctionDecl *D);
   ASTLocation VisitObjCMethodDecl(ObjCMethodDecl *D);
+  ASTLocation VisitTypedefDecl(TypedefDecl *D);
   ASTLocation VisitDecl(Decl *D);
 };
 
@@ -278,6 +282,16 @@
   return ASTLocation(D);
 }
 
+ASTLocation DeclLocResolver::VisitTypedefDecl(TypedefDecl *D) {
+  assert(ContainsLocation(D) &&
+         "Should visit only after verifying that loc is in range");
+
+  if (ContainsLocation(D->getTypeDeclaratorInfo()))
+    return ResolveInDeclarator(D, /*Stmt=*/0, D->getTypeDeclaratorInfo());
+
+  return ASTLocation(D);
+}
+
 ASTLocation DeclLocResolver::VisitVarDecl(VarDecl *D) {
   assert(ContainsLocation(D) &&
          "Should visit only after verifying that loc is in range");
diff --git a/lib/Sema/Sema.cpp b/lib/Sema/Sema.cpp
index fc9c14f..64007f2 100644
--- a/lib/Sema/Sema.cpp
+++ b/lib/Sema/Sema.cpp
@@ -277,15 +277,20 @@
   PushDeclContext(S, Context.getTranslationUnitDecl());
 
   if (PP.getTargetInfo().getPointerWidth(0) >= 64) {
+    DeclaratorInfo *DInfo;
+
     // Install [u]int128_t for 64-bit targets.
+    DInfo = Context.getTrivialDeclaratorInfo(Context.Int128Ty);
     PushOnScopeChains(TypedefDecl::Create(Context, CurContext,
                                           SourceLocation(),
                                           &Context.Idents.get("__int128_t"),
-                                          Context.Int128Ty), TUScope);
+                                          DInfo), TUScope);
+
+    DInfo = Context.getTrivialDeclaratorInfo(Context.UnsignedInt128Ty);
     PushOnScopeChains(TypedefDecl::Create(Context, CurContext,
                                           SourceLocation(),
                                           &Context.Idents.get("__uint128_t"),
-                                          Context.UnsignedInt128Ty), TUScope);
+                                          DInfo), TUScope);
   }
 
 
@@ -298,10 +303,10 @@
     PushOnScopeChains(SelTag, TUScope);
 
     QualType SelT = Context.getPointerType(Context.getTagDeclType(SelTag));
-    TypedefDecl *SelTypedef = TypedefDecl::Create(Context, CurContext,
-                                                  SourceLocation(),
-                                                  &Context.Idents.get("SEL"),
-                                                  SelT);
+    DeclaratorInfo *SelInfo = Context.getTrivialDeclaratorInfo(SelT);
+    TypedefDecl *SelTypedef
+      = TypedefDecl::Create(Context, CurContext, SourceLocation(),
+                            &Context.Idents.get("SEL"), SelInfo);
     PushOnScopeChains(SelTypedef, TUScope);
     Context.setObjCSelType(Context.getTypeDeclType(SelTypedef));
   }
@@ -317,22 +322,23 @@
   }
   // Create the built-in typedef for 'id'.
   if (Context.getObjCIdType().isNull()) {
-    TypedefDecl *IdTypedef =
-      TypedefDecl::Create(
-        Context, CurContext, SourceLocation(), &Context.Idents.get("id"),
-        Context.getObjCObjectPointerType(Context.ObjCBuiltinIdTy)
-      );
+    QualType IdT = Context.getObjCObjectPointerType(Context.ObjCBuiltinIdTy);
+    DeclaratorInfo *IdInfo = Context.getTrivialDeclaratorInfo(IdT);
+    TypedefDecl *IdTypedef
+      = TypedefDecl::Create(Context, CurContext, SourceLocation(),
+                            &Context.Idents.get("id"), IdInfo);
     PushOnScopeChains(IdTypedef, TUScope);
     Context.setObjCIdType(Context.getTypeDeclType(IdTypedef));
     Context.ObjCIdRedefinitionType = Context.getObjCIdType();
   }
   // Create the built-in typedef for 'Class'.
   if (Context.getObjCClassType().isNull()) {
-    TypedefDecl *ClassTypedef =
-      TypedefDecl::Create(
-        Context, CurContext, SourceLocation(), &Context.Idents.get("Class"),
-        Context.getObjCObjectPointerType(Context.ObjCBuiltinClassTy)
-      );
+    QualType ClassType
+      = Context.getObjCObjectPointerType(Context.ObjCBuiltinClassTy);
+    DeclaratorInfo *ClassInfo = Context.getTrivialDeclaratorInfo(ClassType);
+    TypedefDecl *ClassTypedef
+      = TypedefDecl::Create(Context, CurContext, SourceLocation(),
+                            &Context.Idents.get("Class"), ClassInfo);
     PushOnScopeChains(ClassTypedef, TUScope);
     Context.setObjCClassType(Context.getTypeDeclType(ClassTypedef));
     Context.ObjCClassRedefinitionType = Context.getObjCClassType();
diff --git a/lib/Sema/Sema.h b/lib/Sema/Sema.h
index 7f3c49a..5cff7a5 100644
--- a/lib/Sema/Sema.h
+++ b/lib/Sema/Sema.h
@@ -767,7 +767,8 @@
 
 
   /// Subroutines of ActOnDeclarator().
-  TypedefDecl *ParseTypedefDecl(Scope *S, Declarator &D, QualType T);
+  TypedefDecl *ParseTypedefDecl(Scope *S, Declarator &D, QualType T,
+                                DeclaratorInfo *DInfo);
   void MergeTypeDefDecl(TypedefDecl *New, Decl *Old);
   bool MergeFunctionDecl(FunctionDecl *New, Decl *Old);
   bool MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old);
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 98b71c7..1b4c594 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -1986,12 +1986,9 @@
   if (D.getDeclSpec().isThreadSpecified())
     Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread);
 
-  TypedefDecl *NewTD = ParseTypedefDecl(S, D, R);
+  TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, DInfo);
   if (!NewTD) return 0;
 
-  if (D.isInvalidType())
-    NewTD->setInvalidDecl();
-
   // Handle attributes prior to checking for duplicates in MergeVarDecl
   ProcessDeclAttributes(S, NewTD, D);
   // Merge the decl with the existing one if appropriate. If the decl is
@@ -2013,7 +2010,7 @@
           TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative);
       if (!FixedTy.isNull()) {
         Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size);
-        NewTD->setUnderlyingType(FixedTy);
+        NewTD->setTypeDeclaratorInfo(Context.getTrivialDeclaratorInfo(FixedTy));
       } else {
         if (SizeIsNegative)
           Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size);
@@ -4097,15 +4094,21 @@
   }
 }
 
-TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) {
+TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T,
+                                    DeclaratorInfo *DInfo) {
   assert(D.getIdentifier() && "Wrong callback for declspec without declarator");
   assert(!T.isNull() && "GetTypeForDeclarator() returned null type");
 
+  if (!DInfo) {
+    assert(D.isInvalidType() && "no declarator info for valid type");
+    DInfo = Context.getTrivialDeclaratorInfo(T);
+  }
+
   // Scope manipulation handled by caller.
   TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext,
                                            D.getIdentifierLoc(),
                                            D.getIdentifier(),
-                                           T);
+                                           DInfo);
 
   if (const TagType *TT = T->getAs<TagType>()) {
     TagDecl *TD = TT->getDecl();
diff --git a/lib/Sema/SemaDeclAttr.cpp b/lib/Sema/SemaDeclAttr.cpp
index 341d49e..090a6cd 100644
--- a/lib/Sema/SemaDeclAttr.cpp
+++ b/lib/Sema/SemaDeclAttr.cpp
@@ -193,7 +193,8 @@
   // This will run the reguired checks.
   QualType T = S.BuildExtVectorType(curType, S.Owned(sizeExpr), Attr.getLoc());
   if (!T.isNull()) {
-    tDecl->setUnderlyingType(T);
+    // FIXME: preserve the old source info.
+    tDecl->setTypeDeclaratorInfo(S.Context.getTrivialDeclaratorInfo(T));
 
     // Remember this typedef decl, we will need it later for diagnostics.
     S.ExtVectorDecls.push_back(tDecl);
@@ -278,8 +279,11 @@
 
   if (ValueDecl *VD = dyn_cast<ValueDecl>(D))
     VD->setType(CurType);
-  else
-    cast<TypedefDecl>(D)->setUnderlyingType(CurType);
+  else {
+    // FIXME: preserve existing source info.
+    DeclaratorInfo *DInfo = S.Context.getTrivialDeclaratorInfo(CurType);
+    cast<TypedefDecl>(D)->setTypeDeclaratorInfo(DInfo);
+  }
 }
 
 static void HandlePackedAttr(Decl *d, const AttributeList &Attr, Sema &S) {
@@ -1636,9 +1640,10 @@
   }
 
   // Install the new type.
-  if (TypedefDecl *TD = dyn_cast<TypedefDecl>(D))
-    TD->setUnderlyingType(NewTy);
-  else
+  if (TypedefDecl *TD = dyn_cast<TypedefDecl>(D)) {
+    // FIXME: preserve existing source info.
+    TD->setTypeDeclaratorInfo(S.Context.getTrivialDeclaratorInfo(NewTy));
+  } else
     cast<ValueDecl>(D)->setType(NewTy);
 }
 
diff --git a/lib/Sema/SemaTemplateInstantiateDecl.cpp b/lib/Sema/SemaTemplateInstantiateDecl.cpp
index c30f48e..422a7bc 100644
--- a/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -99,20 +99,20 @@
 
 Decl *TemplateDeclInstantiator::VisitTypedefDecl(TypedefDecl *D) {
   bool Invalid = false;
-  QualType T = D->getUnderlyingType();
-  if (T->isDependentType()) {
-    T = SemaRef.SubstType(T, TemplateArgs,
-                          D->getLocation(), D->getDeclName());
-    if (T.isNull()) {
+  DeclaratorInfo *DI = D->getTypeDeclaratorInfo();
+  if (DI->getType()->isDependentType()) {
+    DI = SemaRef.SubstType(DI, TemplateArgs,
+                           D->getLocation(), D->getDeclName());
+    if (!DI) {
       Invalid = true;
-      T = SemaRef.Context.IntTy;
+      DI = SemaRef.Context.getTrivialDeclaratorInfo(SemaRef.Context.IntTy);
     }
   }
 
   // Create the new typedef
   TypedefDecl *Typedef
     = TypedefDecl::Create(SemaRef.Context, Owner, D->getLocation(),
-                          D->getIdentifier(), T);
+                          D->getIdentifier(), DI);
   if (Invalid)
     Typedef->setInvalidDecl();