[C++11] Use 'nullptr'. Sema edition.

llvm-svn: 209613
diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 66afaaa..2a0f56b 100644
--- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -132,7 +132,7 @@
 static void instantiateDependentEnableIfAttr(
     Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,
     const EnableIfAttr *A, const Decl *Tmpl, Decl *New) {
-  Expr *Cond = 0;
+  Expr *Cond = nullptr;
   {
     EnterExpressionEvaluationContext Unevaluated(S, Sema::Unevaluated);
     ExprResult Result = S.SubstExpr(A->getCond(), TemplateArgs);
@@ -187,7 +187,7 @@
     if (TmplAttr->isLateParsed() && LateAttrs) {
       // Late parsed attributes must be instantiated and attached after the
       // enclosing class has been instantiated.  See Sema::InstantiateClass.
-      LocalInstantiationScope *Saved = 0;
+      LocalInstantiationScope *Saved = nullptr;
       if (CurrentInstantiationScope)
         Saved = CurrentInstantiationScope->cloneScopes(OuterMostScope);
       LateAttrs->push_back(LateInstantiatedAttribute(TmplAttr, Saved, New));
@@ -297,7 +297,7 @@
     NamedDecl *InstPrev = SemaRef.FindInstantiatedDecl(D->getLocation(), Prev,
                                                        TemplateArgs);
     if (!InstPrev)
-      return 0;
+      return nullptr;
 
     TypedefNameDecl *InstPrevTypedef = cast<TypedefNameDecl>(InstPrev);
 
@@ -335,11 +335,11 @@
   TemplateParameterList *TempParams = D->getTemplateParameters();
   TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
   if (!InstParams)
-    return 0;
+    return nullptr;
 
   TypeAliasDecl *Pattern = D->getTemplatedDecl();
 
-  TypeAliasTemplateDecl *PrevAliasTemplate = 0;
+  TypeAliasTemplateDecl *PrevAliasTemplate = nullptr;
   if (Pattern->getPreviousDecl()) {
     DeclContext::lookup_result Found = Owner->lookup(Pattern->getDeclName());
     if (!Found.empty()) {
@@ -350,7 +350,7 @@
   TypeAliasDecl *AliasInst = cast_or_null<TypeAliasDecl>(
     InstantiateTypedefNameDecl(Pattern, /*IsTypeAlias=*/true));
   if (!AliasInst)
-    return 0;
+    return nullptr;
 
   TypeAliasTemplateDecl *Inst
     = TypeAliasTemplateDecl::Create(SemaRef.Context, Owner, D->getLocation(),
@@ -380,7 +380,7 @@
   if (const RecordType *RecordTy = D->getType()->getAs<RecordType>())
     if (RecordTy->getDecl()->isAnonymousStructOrUnion())
       if (!VisitCXXRecordDecl(cast<CXXRecordDecl>(RecordTy->getDecl())))
-        return 0;
+        return nullptr;
 
   // Do substitution on the type of the declaration
   TypeSourceInfo *DI = SemaRef.SubstType(D->getTypeSourceInfo(),
@@ -388,12 +388,12 @@
                                          D->getTypeSpecStartLoc(),
                                          D->getDeclName());
   if (!DI)
-    return 0;
+    return nullptr;
 
   if (DI->getType()->isFunctionType()) {
     SemaRef.Diag(D->getLocation(), diag::err_variable_instantiates_to_function)
       << D->isStaticDataMember() << DI->getType();
-    return 0;
+    return nullptr;
   }
 
   DeclContext *DC = Owner;
@@ -412,7 +412,7 @@
 
   // Substitute the nested name specifier, if any.
   if (SubstQualifier(D, Var))
-    return 0;
+    return nullptr;
 
   SemaRef.BuildVariableInstantiation(Var, D, TemplateArgs, LateAttrs, Owner,
                                      StartingScope, InstantiatingVarTemplate);
@@ -461,7 +461,7 @@
 
   Expr *BitWidth = D->getBitWidth();
   if (Invalid)
-    BitWidth = 0;
+    BitWidth = nullptr;
   else if (BitWidth) {
     // The bit-width expression is a constant expression.
     EnterExpressionEvaluationContext Unevaluated(SemaRef,
@@ -471,7 +471,7 @@
       = SemaRef.SubstExpr(BitWidth, TemplateArgs);
     if (InstantiatedBitWidth.isInvalid()) {
       Invalid = true;
-      BitWidth = 0;
+      BitWidth = nullptr;
     } else
       BitWidth = InstantiatedBitWidth.takeAs<Expr>();
   }
@@ -485,10 +485,10 @@
                                             D->getInClassInitStyle(),
                                             D->getInnerLocStart(),
                                             D->getAccess(),
-                                            0);
+                                            nullptr);
   if (!Field) {
     cast<Decl>(Owner)->setInvalidDecl();
-    return 0;
+    return nullptr;
   }
 
   SemaRef.InstantiateAttrs(TemplateArgs, D, Field, LateAttrs, StartingScope);
@@ -570,7 +570,7 @@
     NamedDecl *Next = SemaRef.FindInstantiatedDecl(D->getLocation(), PI,
                                               TemplateArgs);
     if (!Next)
-      return 0;
+      return nullptr;
 
     NamedChain[i++] = Next;
   }
@@ -604,12 +604,12 @@
                                  D->getLocation(), DeclarationName());
     }
     if (!InstTy)
-      return 0;
+      return nullptr;
 
     FriendDecl *FD = SemaRef.CheckFriendTypeDecl(D->getLocStart(),
                                                  D->getFriendLoc(), InstTy);
     if (!FD)
-      return 0;
+      return nullptr;
 
     FD->setAccess(AS_public);
     FD->setUnsupportedFriend(D->isUnsupportedFriend());
@@ -625,7 +625,7 @@
   // objects, with the most important detail being that the target
   // decl should almost certainly not be placed in Owner.
   Decl *NewND = Visit(ND);
-  if (!NewND) return 0;
+  if (!NewND) return nullptr;
 
   FriendDecl *FD =
     FriendDecl::Create(SemaRef.Context, Owner, D->getLocation(),
@@ -646,7 +646,7 @@
   ExprResult InstantiatedAssertExpr
     = SemaRef.SubstExpr(AssertExpr, TemplateArgs);
   if (InstantiatedAssertExpr.isInvalid())
-    return 0;
+    return nullptr;
 
   return SemaRef.BuildStaticAssertDeclaration(D->getLocation(),
                                               InstantiatedAssertExpr.get(),
@@ -656,12 +656,12 @@
 }
 
 Decl *TemplateDeclInstantiator::VisitEnumDecl(EnumDecl *D) {
-  EnumDecl *PrevDecl = 0;
+  EnumDecl *PrevDecl = nullptr;
   if (D->getPreviousDecl()) {
     NamedDecl *Prev = SemaRef.FindInstantiatedDecl(D->getLocation(),
                                                    D->getPreviousDecl(),
                                                    TemplateArgs);
-    if (!Prev) return 0;
+    if (!Prev) return nullptr;
     PrevDecl = cast<EnumDecl>(Prev);
   }
 
@@ -694,7 +694,7 @@
   Enum->setAccess(D->getAccess());
   // Forward the mangling number from the template to the instantiated decl.
   SemaRef.Context.setManglingNumber(Enum, SemaRef.Context.getManglingNumber(D));
-  if (SubstQualifier(D, Enum)) return 0;
+  if (SubstQualifier(D, Enum)) return nullptr;
   Owner->addDecl(Enum);
 
   EnumDecl *Def = D->getDefinition();
@@ -736,10 +736,10 @@
 
   SmallVector<Decl*, 4> Enumerators;
 
-  EnumConstantDecl *LastEnumConst = 0;
+  EnumConstantDecl *LastEnumConst = nullptr;
   for (auto *EC : Pattern->enumerators()) {
     // The specified value for the enumerator.
-    ExprResult Value = SemaRef.Owned((Expr *)0);
+    ExprResult Value = SemaRef.Owned((Expr *)nullptr);
     if (Expr *UninstValue = EC->getInitExpr()) {
       // The enumerator's value expression is a constant expression.
       EnterExpressionEvaluationContext Unevaluated(SemaRef,
@@ -751,7 +751,7 @@
     // Drop the initial value and continue.
     bool isInvalid = false;
     if (Value.isInvalid()) {
-      Value = SemaRef.Owned((Expr *)0);
+      Value = SemaRef.Owned((Expr *)nullptr);
       isInvalid = true;
     }
 
@@ -787,7 +787,7 @@
   SemaRef.ActOnEnumBody(Enum->getLocation(), SourceLocation(),
                         Enum->getRBraceLoc(), Enum,
                         Enumerators,
-                        0, 0);
+                        nullptr, nullptr);
 }
 
 Decl *TemplateDeclInstantiator::VisitEnumConstantDecl(EnumConstantDecl *D) {
@@ -803,7 +803,7 @@
   TemplateParameterList *TempParams = D->getTemplateParameters();
   TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
   if (!InstParams)
-    return NULL;
+    return nullptr;
 
   CXXRecordDecl *Pattern = D->getTemplatedDecl();
 
@@ -815,11 +815,11 @@
     QualifierLoc = SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc,
                                                        TemplateArgs);
     if (!QualifierLoc)
-      return 0;
+      return nullptr;
   }
 
-  CXXRecordDecl *PrevDecl = 0;
-  ClassTemplateDecl *PrevClassTemplate = 0;
+  CXXRecordDecl *PrevDecl = nullptr;
+  ClassTemplateDecl *PrevClassTemplate = nullptr;
 
   if (!isFriend && Pattern->getPreviousDecl()) {
     DeclContext::lookup_result Found = Owner->lookup(Pattern->getDeclName());
@@ -840,7 +840,7 @@
       CXXScopeSpec SS;
       SS.Adopt(QualifierLoc);
       DC = SemaRef.computeDeclContext(SS);
-      if (!DC) return 0;
+      if (!DC) return nullptr;
     } else {
       DC = SemaRef.FindInstantiatedContext(Pattern->getLocation(),
                                            Pattern->getDeclContext(),
@@ -863,7 +863,7 @@
       SemaRef.Diag(Pattern->getLocation(), diag::err_not_tag_in_scope)
         << D->getTemplatedDecl()->getTagKind() << Pattern->getDeclName() << DC
         << QualifierLoc.getSourceRange();
-      return 0;
+      return nullptr;
     }
 
     bool AdoptedPreviousTemplateParams = false;
@@ -902,7 +902,7 @@
                                                   Complain,
                                                   Sema::TPL_TemplateMatch)) {
         if (Complain)
-          return 0;
+          return nullptr;
 
         AdoptedPreviousTemplateParams = true;
         InstParams = PrevParams;
@@ -913,7 +913,7 @@
       if (!AdoptedPreviousTemplateParams &&
           SemaRef.CheckTemplateParameterList(InstParams, PrevParams,
                                              Sema::TPC_ClassTemplate))
-        return 0;
+        return nullptr;
     }
   }
 
@@ -990,12 +990,12 @@
   DeclContext::lookup_result Found
     = Owner->lookup(ClassTemplate->getDeclName());
   if (Found.empty())
-    return 0;
+    return nullptr;
 
   ClassTemplateDecl *InstClassTemplate
     = dyn_cast<ClassTemplateDecl>(Found.front());
   if (!InstClassTemplate)
-    return 0;
+    return nullptr;
 
   if (ClassTemplatePartialSpecializationDecl *Result
         = InstClassTemplate->findPartialSpecInstantiatedFromMember(D))
@@ -1014,10 +1014,10 @@
   TemplateParameterList *TempParams = D->getTemplateParameters();
   TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
   if (!InstParams)
-    return NULL;
+    return nullptr;
 
   VarDecl *Pattern = D->getTemplatedDecl();
-  VarTemplateDecl *PrevVarTemplate = 0;
+  VarTemplateDecl *PrevVarTemplate = nullptr;
 
   if (Pattern->getPreviousDecl()) {
     DeclContext::lookup_result Found = Owner->lookup(Pattern->getDeclName());
@@ -1095,9 +1095,9 @@
   TemplateParameterList *TempParams = D->getTemplateParameters();
   TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
   if (!InstParams)
-    return NULL;
+    return nullptr;
 
-  FunctionDecl *Instantiated = 0;
+  FunctionDecl *Instantiated = nullptr;
   if (CXXMethodDecl *DMethod = dyn_cast<CXXMethodDecl>(D->getTemplatedDecl()))
     Instantiated = cast_or_null<FunctionDecl>(VisitCXXMethodDecl(DMethod,
                                                                  InstParams));
@@ -1107,7 +1107,7 @@
                                                                 InstParams));
 
   if (!Instantiated)
-    return 0;
+    return nullptr;
 
   // Link the instantiated function template declaration to the function
   // template from which it was instantiated.
@@ -1137,14 +1137,14 @@
 }
 
 Decl *TemplateDeclInstantiator::VisitCXXRecordDecl(CXXRecordDecl *D) {
-  CXXRecordDecl *PrevDecl = 0;
+  CXXRecordDecl *PrevDecl = nullptr;
   if (D->isInjectedClassName())
     PrevDecl = cast<CXXRecordDecl>(Owner);
   else if (D->getPreviousDecl()) {
     NamedDecl *Prev = SemaRef.FindInstantiatedDecl(D->getLocation(),
                                                    D->getPreviousDecl(),
                                                    TemplateArgs);
-    if (!Prev) return 0;
+    if (!Prev) return nullptr;
     PrevDecl = cast<CXXRecordDecl>(Prev);
   }
 
@@ -1155,7 +1155,7 @@
 
   // Substitute the nested name specifier, if any.
   if (SubstQualifier(D, Record))
-    return 0;
+    return nullptr;
 
   Record->setImplicit(D->isImplicit());
   // FIXME: Check against AS_none is an ugly hack to work around the issue that
@@ -1230,7 +1230,7 @@
   if (FunctionTemplate && !TemplateParams) {
     ArrayRef<TemplateArgument> Innermost = TemplateArgs.getInnermost();
 
-    void *InsertPos = 0;
+    void *InsertPos = nullptr;
     FunctionDecl *SpecFunc
       = FunctionTemplate->findSpecialization(Innermost.begin(), Innermost.size(),
                                              InsertPos);
@@ -1246,7 +1246,7 @@
   else
     isFriend = (D->getFriendObjectKind() != Decl::FOK_None);
 
-  bool MergeWithParentScope = (TemplateParams != 0) ||
+  bool MergeWithParentScope = (TemplateParams != nullptr) ||
     Owner->isFunctionOrMethod() ||
     !(isa<Decl>(Owner) &&
       cast<Decl>(Owner)->isDefinedOutsideFunctionOrMethod());
@@ -1255,7 +1255,7 @@
   SmallVector<ParmVarDecl *, 4> Params;
   TypeSourceInfo *TInfo = SubstFunctionType(D, Params);
   if (!TInfo)
-    return 0;
+    return nullptr;
   QualType T = adjustFunctionTypeForInstantiation(SemaRef.Context, D, TInfo);
 
   NestedNameSpecifierLoc QualifierLoc = D->getQualifierLoc();
@@ -1263,7 +1263,7 @@
     QualifierLoc = SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc,
                                                        TemplateArgs);
     if (!QualifierLoc)
-      return 0;
+      return nullptr;
   }
 
   // If we're instantiating a local function declaration, put the result
@@ -1277,7 +1277,7 @@
     CXXScopeSpec SS;
     SS.Adopt(QualifierLoc);
     DC = SemaRef.computeDeclContext(SS);
-    if (!DC) return 0;
+    if (!DC) return nullptr;
   } else {
     DC = SemaRef.FindInstantiatedContext(D->getLocation(), D->getDeclContext(),
                                          TemplateArgs);
@@ -1351,7 +1351,7 @@
                             TemplateArgumentList::CreateCopy(SemaRef.Context,
                                                              Innermost.begin(),
                                                              Innermost.size()),
-                                                /*InsertPos=*/0);
+                                                /*InsertPos=*/nullptr);
   } else if (isFriend) {
     // Note, we need this connection even if the friend doesn't have a body.
     // Its body may exist but not have been attached yet due to deferred
@@ -1385,14 +1385,14 @@
                                           Info->getRAngleLoc());
     if (SemaRef.Subst(Info->getTemplateArgs(), Info->getNumTemplateArgs(),
                       ExplicitArgs, TemplateArgs))
-      return 0;
+      return nullptr;
 
     // Map the candidate templates to their instantiations.
     for (unsigned I = 0, E = Info->getNumTemplates(); I != E; ++I) {
       Decl *Temp = SemaRef.FindInstantiatedDecl(D->getLocation(),
                                                 Info->getTemplate(I),
                                                 TemplateArgs);
-      if (!Temp) return 0;
+      if (!Temp) return nullptr;
 
       Previous.addDecl(cast<FunctionTemplateDecl>(Temp));
     }
@@ -1418,7 +1418,7 @@
       Previous.clear();
   }
 
-  SemaRef.CheckFunctionDeclaration(/*Scope*/ 0, Function, Previous,
+  SemaRef.CheckFunctionDeclaration(/*Scope*/ nullptr, Function, Previous,
                                    isExplicitSpecialization);
 
   NamedDecl *PrincipalDecl = (TemplateParams
@@ -1441,7 +1441,7 @@
     //   to these implicit definitions.
     if (D->isThisDeclarationADefinition()) {
       // Check for a function body.
-      const FunctionDecl *Definition = 0;
+      const FunctionDecl *Definition = nullptr;
       if (Function->isDefined(Definition) &&
           Definition->getTemplateSpecializationKind() == TSK_Undeclared) {
         SemaRef.Diag(Function->getLocation(), diag::err_redefinition)
@@ -1508,7 +1508,7 @@
     // specialization for this particular set of template arguments.
     ArrayRef<TemplateArgument> Innermost = TemplateArgs.getInnermost();
 
-    void *InsertPos = 0;
+    void *InsertPos = nullptr;
     FunctionDecl *SpecFunc
       = FunctionTemplate->findSpecialization(Innermost.begin(), 
                                              Innermost.size(),
@@ -1525,7 +1525,7 @@
   else
     isFriend = (D->getFriendObjectKind() != Decl::FOK_None);
 
-  bool MergeWithParentScope = (TemplateParams != 0) ||
+  bool MergeWithParentScope = (TemplateParams != nullptr) ||
     !(isa<Decl>(Owner) &&
       cast<Decl>(Owner)->isDefinedOutsideFunctionOrMethod());
   LocalInstantiationScope Scope(SemaRef, MergeWithParentScope);
@@ -1539,7 +1539,7 @@
       TemplateParameterList *TempParams = D->getTemplateParameterList(I);
       TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
       if (!InstParams)
-        return NULL;
+        return nullptr;
       TempParamLists[I] = InstParams;
     }
   }
@@ -1547,7 +1547,7 @@
   SmallVector<ParmVarDecl *, 4> Params;
   TypeSourceInfo *TInfo = SubstFunctionType(D, Params);
   if (!TInfo)
-    return 0;
+    return nullptr;
   QualType T = adjustFunctionTypeForInstantiation(SemaRef.Context, D, TInfo);
 
   NestedNameSpecifierLoc QualifierLoc = D->getQualifierLoc();
@@ -1555,7 +1555,7 @@
     QualifierLoc = SemaRef.SubstNestedNameSpecifierLoc(QualifierLoc,
                                                  TemplateArgs);
     if (!QualifierLoc)
-      return 0;
+      return nullptr;
   }
 
   DeclContext *DC = Owner;
@@ -1566,18 +1566,18 @@
       DC = SemaRef.computeDeclContext(SS);
 
       if (DC && SemaRef.RequireCompleteDeclContext(SS, DC))
-        return 0;
+        return nullptr;
     } else {
       DC = SemaRef.FindInstantiatedContext(D->getLocation(),
                                            D->getDeclContext(),
                                            TemplateArgs);
     }
-    if (!DC) return 0;
+    if (!DC) return nullptr;
   }
 
   // Build the instantiated method declaration.
   CXXRecordDecl *Record = cast<CXXRecordDecl>(DC);
-  CXXMethodDecl *Method = 0;
+  CXXMethodDecl *Method = nullptr;
 
   SourceLocation StartLoc = D->getInnerLocStart();
   DeclarationNameInfo NameInfo
@@ -1603,7 +1603,7 @@
         Sema::InstantiatingTemplate Inst(SemaRef, Constructor->getLocation(),
                                          Inh);
         if (Inst.isInvalid())
-          return 0;
+          return nullptr;
         Sema::ContextRAII SavedContext(SemaRef, Inh->getDeclContext());
         LocalInstantiationScope LocalScope(SemaRef);
 
@@ -1614,7 +1614,7 @@
         Inh = cast_or_null<CXXConstructorDecl>(
             SemaRef.SubstDecl(Inh, Inh->getDeclContext(), InheritedArgs));
         if (!Inh)
-          return 0;
+          return nullptr;
       }
       cast<CXXConstructorDecl>(Method)->setInheritedConstructor(Inh);
     }
@@ -1675,7 +1675,7 @@
                          TemplateArgumentList::CreateCopy(SemaRef.Context,
                                                           Innermost.begin(),
                                                           Innermost.size()),
-                                              /*InsertPos=*/0);
+                                              /*InsertPos=*/nullptr);
   } else if (!isFriend) {
     // Record that this is an instantiation of a member function.
     Method->setInstantiationOfMemberFunction(D, TSK_ImplicitInstantiation);
@@ -1718,7 +1718,7 @@
   }
 
   if (!IsClassScopeSpecialization)
-    SemaRef.CheckFunctionDeclaration(0, Method, Previous, false);
+    SemaRef.CheckFunctionDeclaration(nullptr, Method, Previous, false);
 
   if (D->isPure())
     SemaRef.CheckPureMethod(Method, SourceRange());
@@ -1836,13 +1836,13 @@
                                                D->getLocation(),
                                                D->getDeclName());
       if (!NewDI)
-        return 0;
+        return nullptr;
 
       ExpandedParameterPackTypesAsWritten.push_back(NewDI);
       QualType NewT =SemaRef.CheckNonTypeTemplateParameterType(NewDI->getType(),
                                                               D->getLocation());
       if (NewT.isNull())
-        return 0;
+        return nullptr;
       ExpandedParameterPackTypes.push_back(NewT);
     }
 
@@ -1871,7 +1871,7 @@
                                                 TemplateArgs,
                                                 Expand, RetainExpansion,
                                                 NumExpansions))
-      return 0;
+      return nullptr;
 
     if (Expand) {
       for (unsigned I = 0; I != *NumExpansions; ++I) {
@@ -1880,14 +1880,14 @@
                                                   D->getLocation(),
                                                   D->getDeclName());
         if (!NewDI)
-          return 0;
+          return nullptr;
 
         ExpandedParameterPackTypesAsWritten.push_back(NewDI);
         QualType NewT = SemaRef.CheckNonTypeTemplateParameterType(
                                                               NewDI->getType(),
                                                               D->getLocation());
         if (NewT.isNull())
-          return 0;
+          return nullptr;
         ExpandedParameterPackTypes.push_back(NewT);
       }
 
@@ -1905,12 +1905,12 @@
                                                      D->getLocation(),
                                                      D->getDeclName());
       if (!NewPattern)
-        return 0;
+        return nullptr;
 
       DI = SemaRef.CheckPackExpansion(NewPattern, Expansion.getEllipsisLoc(),
                                       NumExpansions);
       if (!DI)
-        return 0;
+        return nullptr;
 
       T = DI->getType();
     }
@@ -1919,7 +1919,7 @@
     DI = SemaRef.SubstType(D->getTypeSourceInfo(), TemplateArgs,
                            D->getLocation(), D->getDeclName());
     if (!DI)
-      return 0;
+      return nullptr;
 
     // Check that this type is acceptable for a non-type template parameter.
     T = SemaRef.CheckNonTypeTemplateParameterType(DI->getType(),
@@ -2005,7 +2005,7 @@
       TemplateParameterList *Expansion =
         SubstTemplateParams(D->getExpansionTemplateParameters(I));
       if (!Expansion)
-        return 0;
+        return nullptr;
       ExpandedParams.push_back(Expansion);
     }
 
@@ -2030,7 +2030,7 @@
                                                 TemplateArgs,
                                                 Expand, RetainExpansion,
                                                 NumExpansions))
-      return 0;
+      return nullptr;
 
     if (Expand) {
       for (unsigned I = 0; I != *NumExpansions; ++I) {
@@ -2038,7 +2038,7 @@
         LocalInstantiationScope Scope(SemaRef);
         TemplateParameterList *Expansion = SubstTemplateParams(TempParams);
         if (!Expansion)
-          return 0;
+          return nullptr;
         ExpandedParams.push_back(Expansion);
       }
 
@@ -2055,7 +2055,7 @@
       LocalInstantiationScope Scope(SemaRef);
       InstParams = SubstTemplateParams(TempParams);
       if (!InstParams)
-        return 0;
+        return nullptr;
     }
   } else {
     // Perform the actual substitution of template parameters within a new,
@@ -2063,7 +2063,7 @@
     LocalInstantiationScope Scope(SemaRef);
     InstParams = SubstTemplateParams(TempParams);
     if (!InstParams)
-      return 0;
+      return nullptr;
   }
 
   // Build the template template parameter.
@@ -2140,7 +2140,7 @@
     = SemaRef.SubstNestedNameSpecifierLoc(D->getQualifierLoc(),
                                           TemplateArgs);
   if (!QualifierLoc)
-    return 0;
+    return nullptr;
 
   // The name info is non-dependent, so no transformation
   // is required.
@@ -2200,9 +2200,9 @@
         cast_or_null<NamedDecl>(SemaRef.FindInstantiatedDecl(
             Shadow->getLocation(), Shadow->getTargetDecl(), TemplateArgs));
     if (!InstTarget)
-      return 0;
+      return nullptr;
 
-    UsingShadowDecl *PrevDecl = 0;
+    UsingShadowDecl *PrevDecl = nullptr;
     if (CheckRedeclaration) {
       if (SemaRef.CheckUsingShadowDecl(NewUD, InstTarget, Prev, PrevDecl))
         continue;
@@ -2212,7 +2212,8 @@
     }
 
     UsingShadowDecl *InstShadow =
-        SemaRef.BuildUsingShadowDecl(/*Scope*/0, NewUD, InstTarget, PrevDecl);
+        SemaRef.BuildUsingShadowDecl(/*Scope*/nullptr, NewUD, InstTarget,
+                                     PrevDecl);
     SemaRef.Context.setInstantiatedFromUsingShadowDecl(InstShadow, Shadow);
 
     if (isFunctionScope)
@@ -2224,7 +2225,7 @@
 
 Decl *TemplateDeclInstantiator::VisitUsingShadowDecl(UsingShadowDecl *D) {
   // Ignore these;  we handle them in bulk when processing the UsingDecl.
-  return 0;
+  return nullptr;
 }
 
 Decl * TemplateDeclInstantiator
@@ -2233,7 +2234,7 @@
     = SemaRef.SubstNestedNameSpecifierLoc(D->getQualifierLoc(),
                                           TemplateArgs);
   if (!QualifierLoc)
-    return 0;
+    return nullptr;
 
   CXXScopeSpec SS;
   SS.Adopt(QualifierLoc);
@@ -2242,8 +2243,8 @@
   // Hence, no transformation is required for it.
   DeclarationNameInfo NameInfo(D->getDeclName(), D->getLocation());
   NamedDecl *UD =
-    SemaRef.BuildUsingDeclaration(/*Scope*/ 0, D->getAccess(),
-                                  D->getUsingLoc(), SS, NameInfo, 0,
+    SemaRef.BuildUsingDeclaration(/*Scope*/ nullptr, D->getAccess(),
+                                  D->getUsingLoc(), SS, NameInfo, nullptr,
                                   /*instantiation*/ true,
                                   /*typename*/ true, D->getTypenameLoc());
   if (UD)
@@ -2257,7 +2258,7 @@
   NestedNameSpecifierLoc QualifierLoc
       = SemaRef.SubstNestedNameSpecifierLoc(D->getQualifierLoc(), TemplateArgs);
   if (!QualifierLoc)
-    return 0;
+    return nullptr;
 
   CXXScopeSpec SS;
   SS.Adopt(QualifierLoc);
@@ -2266,8 +2267,8 @@
     = SemaRef.SubstDeclarationNameInfo(D->getNameInfo(), TemplateArgs);
 
   NamedDecl *UD =
-    SemaRef.BuildUsingDeclaration(/*Scope*/ 0, D->getAccess(),
-                                  D->getUsingLoc(), SS, NameInfo, 0,
+    SemaRef.BuildUsingDeclaration(/*Scope*/ nullptr, D->getAccess(),
+                                  D->getUsingLoc(), SS, NameInfo, nullptr,
                                   /*instantiation*/ true,
                                   /*typename*/ false, SourceLocation());
   if (UD)
@@ -2281,13 +2282,13 @@
                                      ClassScopeFunctionSpecializationDecl *Decl) {
   CXXMethodDecl *OldFD = Decl->getSpecialization();
   CXXMethodDecl *NewFD = cast<CXXMethodDecl>(VisitCXXMethodDecl(OldFD,
-                                                                0, true));
+                                                                nullptr, true));
 
   LookupResult Previous(SemaRef, NewFD->getNameInfo(), Sema::LookupOrdinaryName,
                         Sema::ForRedeclaration);
 
   TemplateArgumentListInfo TemplateArgs;
-  TemplateArgumentListInfo* TemplateArgsPtr = 0;
+  TemplateArgumentListInfo *TemplateArgsPtr = nullptr;
   if (Decl->hasExplicitTemplateArgs()) {
     TemplateArgs = Decl->templateArgs();
     TemplateArgsPtr = &TemplateArgs;
@@ -2327,11 +2328,11 @@
 }
 
 Decl *TemplateDeclInstantiator::VisitFunctionDecl(FunctionDecl *D) {
-  return VisitFunctionDecl(D, 0);
+  return VisitFunctionDecl(D, nullptr);
 }
 
 Decl *TemplateDeclInstantiator::VisitCXXMethodDecl(CXXMethodDecl *D) {
-  return VisitCXXMethodDecl(D, 0);
+  return VisitCXXMethodDecl(D, nullptr);
 }
 
 Decl *TemplateDeclInstantiator::VisitRecordDecl(RecordDecl *D) {
@@ -2354,11 +2355,11 @@
   DeclContext::lookup_result Found
     = Owner->lookup(ClassTemplate->getDeclName());
   if (Found.empty())
-    return 0;
+    return nullptr;
   ClassTemplateDecl *InstClassTemplate
     = dyn_cast<ClassTemplateDecl>(Found.front());
   if (!InstClassTemplate)
-    return 0;
+    return nullptr;
 
   // Substitute into the template arguments of the class template explicit
   // specialization.
@@ -2371,7 +2372,7 @@
     ArgLocs.push_back(Loc.getArgLoc(I));
   if (SemaRef.Subst(ArgLocs.data(), ArgLocs.size(),
                     InstTemplateArgs, TemplateArgs))
-    return 0;
+    return nullptr;
 
   // Check that the template argument list is well-formed for this
   // class template.
@@ -2381,11 +2382,11 @@
                                         InstTemplateArgs,
                                         false,
                                         Converted))
-    return 0;
+    return nullptr;
 
   // Figure out where to insert this class template explicit specialization
   // in the member template's set of class template explicit specializations.
-  void *InsertPos = 0;
+  void *InsertPos = nullptr;
   ClassTemplateSpecializationDecl *PrevDecl =
       InstClassTemplate->findSpecialization(Converted.data(), Converted.size(),
                                             InsertPos);
@@ -2400,7 +2401,7 @@
                                                      PrevDecl->getSpecializationKind(),
                                                      PrevDecl->getPointOfInstantiation(),
                                                      Ignored))
-    return 0;
+    return nullptr;
 
   // If PrevDecl was a definition and D is also a definition, diagnose.
   // This happens in cases like:
@@ -2419,7 +2420,7 @@
     SemaRef.Diag(D->getLocation(), diag::err_redefinition) << PrevDecl;
     SemaRef.Diag(PrevDecl->getDefinition()->getLocation(),
                  diag::note_previous_definition);
-    return 0;
+    return nullptr;
   }
 
   // Create the class template partial specialization declaration.
@@ -2441,7 +2442,7 @@
 
   // Substitute the nested name specifier, if any.
   if (SubstQualifier(D, InstD))
-    return 0;
+    return nullptr;
 
   // Build the canonical type that describes the converted template
   // arguments of the class template explicit specialization.
@@ -2476,7 +2477,7 @@
       SemaRef.InstantiateClass(D->getLocation(), InstD, D, TemplateArgs,
                                TSK_ImplicitInstantiation,
                                /*Complain=*/true))
-    return 0;
+    return nullptr;
 
   return InstD;
 }
@@ -2496,7 +2497,7 @@
 
   if (SemaRef.Subst(TemplateArgsInfo.getArgumentArray(),
                     TemplateArgsInfo.size(), VarTemplateArgsInfo, TemplateArgs))
-    return 0;
+    return nullptr;
 
   // Check that the template argument list is well-formed for this template.
   SmallVector<TemplateArgument, 4> Converted;
@@ -2504,11 +2505,11 @@
           VarTemplate, VarTemplate->getLocStart(),
           const_cast<TemplateArgumentListInfo &>(VarTemplateArgsInfo), false,
           Converted))
-    return 0;
+    return nullptr;
 
   // Find the variable template specialization declaration that
   // corresponds to these arguments.
-  void *InsertPos = 0;
+  void *InsertPos = nullptr;
   if (VarTemplateSpecializationDecl *VarSpec = VarTemplate->findSpecialization(
           Converted.data(), Converted.size(), InsertPos))
     // If we already have a variable template specialization, return it.
@@ -2528,19 +2529,19 @@
   if (const RecordType *RecordTy = D->getType()->getAs<RecordType>())
     if (RecordTy->getDecl()->isAnonymousStructOrUnion())
       if (!VisitCXXRecordDecl(cast<CXXRecordDecl>(RecordTy->getDecl())))
-        return 0;
+        return nullptr;
 
   // Do substitution on the type of the declaration
   TypeSourceInfo *DI =
       SemaRef.SubstType(D->getTypeSourceInfo(), TemplateArgs,
                         D->getTypeSpecStartLoc(), D->getDeclName());
   if (!DI)
-    return 0;
+    return nullptr;
 
   if (DI->getType()->isFunctionType()) {
     SemaRef.Diag(D->getLocation(), diag::err_variable_instantiates_to_function)
         << D->isStaticDataMember() << DI->getType();
-    return 0;
+    return nullptr;
   }
 
   // Build the instantiated declaration
@@ -2554,7 +2555,7 @@
 
   // Substitute the nested name specifier, if any.
   if (SubstQualifier(D, Var))
-    return 0;
+    return nullptr;
 
   SemaRef.BuildVariableInstantiation(Var, D, TemplateArgs, LateAttrs,
                                      Owner, StartingScope);
@@ -2574,7 +2575,7 @@
   SemaRef.Diag(D->getLocation(), DiagID)
     << D->getDeclKindName();
 
-  return 0;
+  return nullptr;
 }
 
 Decl *TemplateDeclInstantiator::VisitDecl(Decl *D) {
@@ -2585,7 +2586,7 @@
                       const MultiLevelTemplateArgumentList &TemplateArgs) {
   TemplateDeclInstantiator Instantiator(*this, Owner, TemplateArgs);
   if (D->isInvalidDecl())
-    return 0;
+    return nullptr;
 
   return Instantiator.Visit(D);
 }
@@ -2614,7 +2615,7 @@
 
   // Clean up if we had an error.
   if (Invalid)
-    return NULL;
+    return nullptr;
 
   TemplateParameterList *InstL
     = TemplateParameterList::Create(SemaRef.Context, L->getTemplateLoc(),
@@ -2648,7 +2649,7 @@
   TemplateParameterList *TempParams = PartialSpec->getTemplateParameters();
   TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
   if (!InstParams)
-    return 0;
+    return nullptr;
 
   // Substitute into the template arguments of the class template partial
   // specialization.
@@ -2659,7 +2660,7 @@
   if (SemaRef.Subst(TemplArgInfo->getTemplateArgs(),
                     TemplArgInfo->NumTemplateArgs,
                     InstTemplateArgs, TemplateArgs))
-    return 0;
+    return nullptr;
 
   // Check that the template argument list is well-formed for this
   // class template.
@@ -2669,11 +2670,11 @@
                                         InstTemplateArgs,
                                         false,
                                         Converted))
-    return 0;
+    return nullptr;
 
   // Figure out where to insert this class template partial specialization
   // in the member template's set of class template partial specializations.
-  void *InsertPos = 0;
+  void *InsertPos = nullptr;
   ClassTemplateSpecializationDecl *PrevDecl
     = ClassTemplate->findPartialSpecialization(Converted.data(),
                                                Converted.size(), InsertPos);
@@ -2719,7 +2720,7 @@
       << WrittenTy->getType();
     SemaRef.Diag(PrevDecl->getLocation(), diag::note_prev_partial_spec_here)
       << SemaRef.Context.getTypeDeclType(PrevDecl);
-    return 0;
+    return nullptr;
   }
 
 
@@ -2736,17 +2737,18 @@
                                                      Converted.size(),
                                                      InstTemplateArgs,
                                                      CanonType,
-                                                     0);
+                                                     nullptr);
   // Substitute the nested name specifier, if any.
   if (SubstQualifier(PartialSpec, InstPartialSpec))
-    return 0;
+    return nullptr;
 
   InstPartialSpec->setInstantiatedFromMember(PartialSpec);
   InstPartialSpec->setTypeAsWritten(WrittenTy);
 
   // Add this partial specialization to the set of class template partial
   // specializations.
-  ClassTemplate->AddPartialSpecialization(InstPartialSpec, /*InsertPos=*/0);
+  ClassTemplate->AddPartialSpecialization(InstPartialSpec,
+                                          /*InsertPos=*/nullptr);
   return InstPartialSpec;
 }
 
@@ -2775,7 +2777,7 @@
   TemplateParameterList *TempParams = PartialSpec->getTemplateParameters();
   TemplateParameterList *InstParams = SubstTemplateParams(TempParams);
   if (!InstParams)
-    return 0;
+    return nullptr;
 
   // Substitute into the template arguments of the variable template partial
   // specialization.
@@ -2786,18 +2788,18 @@
   if (SemaRef.Subst(TemplArgInfo->getTemplateArgs(),
                     TemplArgInfo->NumTemplateArgs,
                     InstTemplateArgs, TemplateArgs))
-    return 0;
+    return nullptr;
 
   // Check that the template argument list is well-formed for this
   // class template.
   SmallVector<TemplateArgument, 4> Converted;
   if (SemaRef.CheckTemplateArgumentList(VarTemplate, PartialSpec->getLocation(),
                                         InstTemplateArgs, false, Converted))
-    return 0;
+    return nullptr;
 
   // Figure out where to insert this variable template partial specialization
   // in the member template's set of variable template partial specializations.
-  void *InsertPos = 0;
+  void *InsertPos = nullptr;
   VarTemplateSpecializationDecl *PrevDecl =
       VarTemplate->findPartialSpecialization(Converted.data(), Converted.size(),
                                              InsertPos);
@@ -2839,7 +2841,7 @@
         << WrittenTy->getType();
     SemaRef.Diag(PrevDecl->getLocation(),
                  diag::note_var_prev_partial_spec_here);
-    return 0;
+    return nullptr;
   }
 
   // Do substitution on the type of the declaration
@@ -2847,13 +2849,13 @@
       PartialSpec->getTypeSourceInfo(), TemplateArgs,
       PartialSpec->getTypeSpecStartLoc(), PartialSpec->getDeclName());
   if (!DI)
-    return 0;
+    return nullptr;
 
   if (DI->getType()->isFunctionType()) {
     SemaRef.Diag(PartialSpec->getLocation(),
                  diag::err_variable_instantiates_to_function)
         << PartialSpec->isStaticDataMember() << DI->getType();
-    return 0;
+    return nullptr;
   }
 
   // Create the variable template partial specialization declaration.
@@ -2866,14 +2868,14 @@
 
   // Substitute the nested name specifier, if any.
   if (SubstQualifier(PartialSpec, InstPartialSpec))
-    return 0;
+    return nullptr;
 
   InstPartialSpec->setInstantiatedFromMember(PartialSpec);
   InstPartialSpec->setTypeAsWritten(WrittenTy);
 
   // Add this partial specialization to the set of variable template partial
   // specializations. The instantiation of the initializer is not necessary.
-  VarTemplate->AddPartialSpecialization(InstPartialSpec, /*InsertPos=*/0);
+  VarTemplate->AddPartialSpecialization(InstPartialSpec, /*InsertPos=*/nullptr);
 
   SemaRef.BuildVariableInstantiation(InstPartialSpec, PartialSpec, TemplateArgs,
                                      LateAttrs, Owner, StartingScope);
@@ -2887,8 +2889,8 @@
   TypeSourceInfo *OldTInfo = D->getTypeSourceInfo();
   assert(OldTInfo && "substituting function without type source info");
   assert(Params.empty() && "parameter vector is non-empty at start");
-  
-  CXXRecordDecl *ThisContext = 0;
+
+  CXXRecordDecl *ThisContext = nullptr;
   unsigned ThisTypeQuals = 0;
   if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
     ThisContext = cast<CXXRecordDecl>(Owner);
@@ -2901,7 +2903,7 @@
                                     D->getDeclName(),
                                     ThisContext, ThisTypeQuals);
   if (!NewTInfo)
-    return 0;
+    return nullptr;
 
   TypeLoc OldTL = OldTInfo->getTypeLoc().IgnoreParens();
   if (FunctionProtoTypeLoc OldProtoLoc = OldTL.getAs<FunctionProtoTypeLoc>()) {
@@ -2954,7 +2956,7 @@
         ParmVarDecl *Parm =
             cast_or_null<ParmVarDecl>(VisitParmVarDecl(OldParam));
         if (!Parm)
-          return 0;
+          return nullptr;
         Params.push_back(Parm);
       }
     }
@@ -2973,7 +2975,7 @@
     if (SemaRef.SubstParmTypes(D->getLocation(), D->param_begin(),
                                D->getNumParams(), TemplateArgs, ParamTypes,
                                &Params))
-      return 0;
+      return nullptr;
   }
 
   return NewTInfo;
@@ -3036,7 +3038,7 @@
   //   "pointer to cv-qualifier-seq X" between the optional cv-qualifer-seq
   //   and the end of the function-definition, member-declarator, or 
   //   declarator.    
-  CXXRecordDecl *ThisContext = 0;
+  CXXRecordDecl *ThisContext = nullptr;
   unsigned ThisTypeQuals = 0;
   if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(New)) {
     ThisContext = Method->getParent();
@@ -3118,7 +3120,7 @@
 
     Exceptions.push_back(T);
   }
-  Expr *NoexceptExpr = 0;
+  Expr *NoexceptExpr = nullptr;
   if (Expr *OldNoexceptExpr = Proto->getNoexceptExpr()) {
     EnterExpressionEvaluationContext Unevaluated(SemaRef,
                                                  Sema::ConstantEvaluated);
@@ -3132,7 +3134,7 @@
           !NoexceptExpr->isValueDependent())
         NoexceptExpr
           = SemaRef.VerifyIntegerConstantExpression(NoexceptExpr,
-              0, diag::err_noexcept_needs_constant_expression,
+              nullptr, diag::err_noexcept_needs_constant_expression,
               /*AllowFold*/ false).take();
     }
   }
@@ -3169,7 +3171,7 @@
   LocalInstantiationScope Scope(*this);
 
   MultiLevelTemplateArgumentList TemplateArgs =
-    getTemplateInstantiationArgs(Decl, 0, /*RelativeToPrimary*/true);
+    getTemplateInstantiationArgs(Decl, nullptr, /*RelativeToPrimary*/true);
 
   FunctionDecl *Template = Proto->getExceptionSpecTemplate();
   addInstantiatedParametersToScope(*this, Decl, Template, Scope, TemplateArgs);
@@ -3415,14 +3417,14 @@
   if (PatternDecl->isDefaulted())
     SetDeclDefaulted(Function, PatternDecl->getLocation());
   else {
-    ActOnStartOfFunctionDef(0, Function);
+    ActOnStartOfFunctionDef(nullptr, Function);
 
     // Enter the scope of this instantiation. We don't use
     // PushDeclContext because we don't have a scope.
     Sema::ContextRAII savedContext(*this, Function);
 
     MultiLevelTemplateArgumentList TemplateArgs =
-      getTemplateInstantiationArgs(Function, 0, false, PatternDecl);
+      getTemplateInstantiationArgs(Function, nullptr, false, PatternDecl);
 
     addInstantiatedParametersToScope(*this, Function, PatternDecl, Scope,
                                      TemplateArgs);
@@ -3488,11 +3490,11 @@
     LateInstantiatedAttrVec *LateAttrs,
     LocalInstantiationScope *StartingScope) {
   if (FromVar->isInvalidDecl())
-    return 0;
+    return nullptr;
 
   InstantiatingTemplate Inst(*this, PointOfInstantiation, FromVar);
   if (Inst.isInvalid())
-    return 0;
+    return nullptr;
 
   MultiLevelTemplateArgumentList TemplateArgLists;
   TemplateArgLists.addOuterTemplateArguments(&TemplateArgList);
@@ -3537,7 +3539,7 @@
       SubstType(PatternDecl->getTypeSourceInfo(), TemplateArgs,
                 PatternDecl->getTypeSpecStartLoc(), PatternDecl->getDeclName());
   if (!DI)
-    return 0;
+    return nullptr;
 
   // Update the type of this variable template specialization.
   VarSpec->setType(DI->getType());
@@ -3725,7 +3727,7 @@
 
   VarTemplateSpecializationDecl *VarSpec =
       dyn_cast<VarTemplateSpecializationDecl>(Var);
-  VarDecl *PatternDecl = 0, *Def = 0;
+  VarDecl *PatternDecl = nullptr, *Def = nullptr;
   MultiLevelTemplateArgumentList TemplateArgs =
       getTemplateInstantiationArgs(Var);
 
@@ -3935,7 +3937,7 @@
     TemplateDeclInstantiator Instantiator(*this, Var->getDeclContext(),
                                           TemplateArgs);
     Var = cast_or_null<VarDecl>(Instantiator.VisitVarTemplateSpecializationDecl(
-        VarSpec->getSpecializedTemplate(), Def, 0,
+        VarSpec->getSpecializedTemplate(), Def, nullptr,
         VarSpec->getTemplateArgsInfo(), VarSpec->getTemplateArgs().asArray()));
     if (Var) {
       llvm::PointerUnion<VarTemplateDecl *,
@@ -4335,7 +4337,7 @@
     if (isInstantiationOf(Ctx, D, *first))
       return cast<NamedDecl>(*first);
 
-  return 0;
+  return nullptr;
 }
 
 /// \brief Finds the instantiation of the given declaration context
@@ -4425,7 +4427,7 @@
       return D;
 
     if (D->isInvalidDecl())
-      return 0;
+      return nullptr;
 
     // If we didn't find the decl, then we must have a label decl that hasn't
     // been found yet.  Lazily instantiate it and return it now.
@@ -4509,7 +4511,7 @@
 
   ParentDC = FindInstantiatedContext(Loc, ParentDC, TemplateArgs);
   if (!ParentDC)
-    return 0;
+    return nullptr;
 
   if (ParentDC != D->getDeclContext()) {
     // We performed some kind of instantiation in the parent context,
@@ -4528,13 +4530,13 @@
           IsBeingInstantiated = true;
         if (!Tag->isBeingDefined() &&
             RequireCompleteType(Loc, T, diag::err_incomplete_type))
-          return 0;
+          return nullptr;
 
         ParentDC = Tag->getDecl();
       }
     }
 
-    NamedDecl *Result = 0;
+    NamedDecl *Result = nullptr;
     if (D->getDeclName()) {
       DeclContext::lookup_result Found = ParentDC->lookup(D->getDeclName());
       Result = findInstantiationOf(Context, D, Found.begin(), Found.end());