Update Clang for 3.5 rebase (r209713).

Change-Id: I8c9133b0f8f776dc915f270b60f94962e771bc83
diff --git a/lib/Sema/SemaTemplateInstantiate.cpp b/lib/Sema/SemaTemplateInstantiate.cpp
index 1ee3e4b..fae1222 100644
--- a/lib/Sema/SemaTemplateInstantiate.cpp
+++ b/lib/Sema/SemaTemplateInstantiate.cpp
@@ -532,8 +532,8 @@
       std::string Name;
       if (!Parm->getName().empty())
         Name = std::string(" '") + Parm->getName().str() + "'";
-                    
-      TemplateParameterList *TemplateParams = 0;
+
+      TemplateParameterList *TemplateParams = nullptr;
       if (TemplateDecl *Template = dyn_cast<TemplateDecl>(Active->Template))
         TemplateParams = Template->getTemplateParameters();
       else
@@ -552,7 +552,7 @@
     }
 
     case ActiveTemplateInstantiation::DefaultTemplateArgumentChecking: {
-      TemplateParameterList *TemplateParams = 0;
+      TemplateParameterList *TemplateParams = nullptr;
       if (TemplateDecl *Template = dyn_cast<TemplateDecl>(Active->Template))
         TemplateParams = Template->getTemplateParameters();
       else
@@ -581,7 +581,7 @@
 
 Optional<TemplateDeductionInfo *> Sema::isSFINAEContext() const {
   if (InNonInstantiationSFINAEContext)
-    return Optional<TemplateDeductionInfo *>(0);
+    return Optional<TemplateDeductionInfo *>(nullptr);
 
   for (SmallVectorImpl<ActiveTemplateInstantiation>::const_reverse_iterator
          Active = ActiveTemplateInstantiations.rbegin(),
@@ -761,11 +761,11 @@
                                    NestedNameSpecifierLoc QualifierLoc,
                                    QualType T);
 
-    TemplateName TransformTemplateName(CXXScopeSpec &SS,
-                                       TemplateName Name,
-                                       SourceLocation NameLoc,                                     
-                                       QualType ObjectType = QualType(),
-                                       NamedDecl *FirstQualifierInScope = 0);
+    TemplateName
+    TransformTemplateName(CXXScopeSpec &SS, TemplateName Name,
+                          SourceLocation NameLoc,
+                          QualType ObjectType = QualType(),
+                          NamedDecl *FirstQualifierInScope = nullptr);
 
     ExprResult TransformPredefinedExpr(PredefinedExpr *E);
     ExprResult TransformDeclRefExpr(DeclRefExpr *E);
@@ -885,7 +885,7 @@
 
 Decl *TemplateInstantiator::TransformDecl(SourceLocation Loc, Decl *D) {
   if (!D)
-    return 0;
+    return nullptr;
 
   if (TemplateTemplateParmDecl *TTP = dyn_cast<TemplateTemplateParmDecl>(D)) {
     if (TTP->getDepth() < TemplateArgs.getNumLevels()) {
@@ -921,7 +921,7 @@
 Decl *TemplateInstantiator::TransformDefinition(SourceLocation Loc, Decl *D) {
   Decl *Inst = getSema().SubstDecl(D, getSema().CurContext, TemplateArgs);
   if (!Inst)
-    return 0;
+    return nullptr;
 
   getSema().CurrentInstantiationScope->InstantiatedLocal(D, Inst);
   return Inst;
@@ -945,8 +945,8 @@
                "Missing argument pack");
         
         if (getSema().ArgumentPackSubstitutionIndex == -1)
-          return 0;
-        
+          return nullptr;
+
         Arg = getPackSubstitutedTemplateArgument(getSema(), Arg);
       }
 
@@ -959,7 +959,7 @@
       
       // The resulting type is not a tag; complain.
       getSema().Diag(Loc, diag::err_nested_name_spec_non_tag) << T;
-      return 0;
+      return nullptr;
     }
   }
   
@@ -1155,7 +1155,7 @@
         return ExprError();
     } else {
       // Propagate NULL template argument.
-      VD = 0;
+      VD = nullptr;
     }
     
     // Derive the type we want the substituted decl to have.  This had
@@ -1393,7 +1393,7 @@
   // the template parameter list of a member template inside the
   // template we are instantiating). Create a new template type
   // parameter with the template "level" reduced by one.
-  TemplateTypeParmDecl *NewTTPDecl = 0;
+  TemplateTypeParmDecl *NewTTPDecl = nullptr;
   if (TemplateTypeParmDecl *OldTTPDecl = T->getDecl())
     NewTTPDecl = cast_or_null<TemplateTypeParmDecl>(
                                   TransformDecl(TL.getNameLoc(), OldTTPDecl));
@@ -1486,7 +1486,7 @@
          "instantiation stack");
   
   if (TL.getType().isNull())
-    return 0;
+    return nullptr;
 
   if (!TL.getType()->isInstantiationDependentType() && 
       !TL.getType()->isVariablyModifiedType()) {
@@ -1502,7 +1502,7 @@
   TLB.reserve(TL.getFullDataSize());
   QualType Result = Instantiator.TransformType(TLB, TL);
   if (Result.isNull())
-    return 0;
+    return nullptr;
 
   return TLB.getTypeSourceInfo(Context, Result);
 }
@@ -1588,7 +1588,7 @@
     Result = Instantiator.TransformType(TLB, TL);
   }
   if (Result.isNull())
-    return 0;
+    return nullptr;
 
   return TLB.getTypeSourceInfo(Context, Result);
 }
@@ -1599,8 +1599,8 @@
                                     Optional<unsigned> NumExpansions,
                                     bool ExpectParameterPack) {
   TypeSourceInfo *OldDI = OldParm->getTypeSourceInfo();
-  TypeSourceInfo *NewDI = 0;
-  
+  TypeSourceInfo *NewDI = nullptr;
+
   TypeLoc OldTL = OldDI->getTypeLoc();
   if (PackExpansionTypeLoc ExpansionTL = OldTL.getAs<PackExpansionTypeLoc>()) {
 
@@ -1609,8 +1609,8 @@
     NewDI = SubstType(ExpansionTL.getPatternLoc(), TemplateArgs, 
                       OldParm->getLocation(), OldParm->getDeclName());
     if (!NewDI)
-      return 0;
-        
+      return nullptr;
+
     if (NewDI->getType()->containsUnexpandedParameterPack()) {
       // We still have unexpanded parameter packs, which means that
       // our function parameter is still a function parameter pack.
@@ -1625,7 +1625,7 @@
       Diag(OldParm->getLocation(), 
            diag::err_function_parameter_pack_without_parameter_packs)
         << NewDI->getType();
-      return 0;
+      return nullptr;
     } 
   } else {
     NewDI = SubstType(OldDI, TemplateArgs, OldParm->getLocation(), 
@@ -1633,11 +1633,11 @@
   }
   
   if (!NewDI)
-    return 0;
+    return nullptr;
 
   if (NewDI->getType()->isVoidType()) {
     Diag(OldParm->getLocation(), diag::err_param_with_void_type);
-    return 0;
+    return nullptr;
   }
 
   ParmVarDecl *NewParm = CheckParameter(Context.getTranslationUnitDecl(),
@@ -1647,8 +1647,8 @@
                                         NewDI->getType(), NewDI,
                                         OldParm->getStorageClass());
   if (!NewParm)
-    return 0;
-                                                
+    return nullptr;
+
   // Mark the (new) default argument as uninstantiated (if any).
   if (OldParm->hasUninstantiatedDefaultArg()) {
     Expr *Arg = OldParm->getUninstantiatedDefaultArg();
@@ -1698,8 +1698,9 @@
   
   TemplateInstantiator Instantiator(*this, TemplateArgs, Loc, 
                                     DeclarationName());
-  return Instantiator.TransformFunctionTypeParams(Loc, Params, NumParams, 0,
-                                                  ParamTypes, OutParams);
+  return Instantiator.TransformFunctionTypeParams(Loc, Params, NumParams,
+                                                  nullptr, ParamTypes,
+                                                  OutParams);
 }
 
 /// \brief Perform substitution on the base class specifiers of the
@@ -2012,8 +2013,8 @@
   }
 
   // Finish checking fields.
-  ActOnFields(0, Instantiation->getLocation(), Instantiation, Fields, 
-              SourceLocation(), SourceLocation(), 0);
+  ActOnFields(nullptr, Instantiation->getLocation(), Instantiation, Fields,
+              SourceLocation(), SourceLocation(), nullptr);
   CheckCompletedCXXClass(Instantiation);
 
   // Attach any in-class member initializers now the class is complete.
@@ -2228,7 +2229,7 @@
     return true;
   
   ClassTemplateDecl *Template = ClassTemplateSpec->getSpecializedTemplate();
-  CXXRecordDecl *Pattern = 0;
+  CXXRecordDecl *Pattern = nullptr;
 
   // C++ [temp.class.spec.match]p1:
   //   When a class template is used in a context that requires an
@@ -2369,6 +2370,9 @@
                               CXXRecordDecl *Instantiation,
                         const MultiLevelTemplateArgumentList &TemplateArgs,
                               TemplateSpecializationKind TSK) {
+  // FIXME: We need to notify the ASTMutationListener that we did all of these
+  // things, in case we have an explicit instantiation definition in a PCM, a
+  // module, or preamble, and the declaration is in an imported AST.
   assert(
       (TSK == TSK_ExplicitInstantiationDefinition ||
        TSK == TSK_ExplicitInstantiationDeclaration ||
@@ -2393,28 +2397,27 @@
                                                    SuppressNew) ||
             SuppressNew)
           continue;
-        
-        if (Function->isDefined())
+
+        // C++11 [temp.explicit]p8:
+        //   An explicit instantiation definition that names a class template
+        //   specialization explicitly instantiates the class template
+        //   specialization and is only an explicit instantiation definition
+        //   of members whose definition is visible at the point of
+        //   instantiation.
+        if (TSK == TSK_ExplicitInstantiationDefinition && !Pattern->isDefined())
           continue;
 
-        if (TSK == TSK_ExplicitInstantiationDefinition) {
-          // C++0x [temp.explicit]p8:
-          //   An explicit instantiation definition that names a class template
-          //   specialization explicitly instantiates the class template 
-          //   specialization and is only an explicit instantiation definition 
-          //   of members whose definition is visible at the point of 
-          //   instantiation.
-          if (!Pattern->isDefined())
-            continue;
-        
-          Function->setTemplateSpecializationKind(TSK, PointOfInstantiation);
-                      
+        Function->setTemplateSpecializationKind(TSK, PointOfInstantiation);
+
+        if (Function->isDefined()) {
+          // Let the ASTConsumer know that this function has been explicitly
+          // instantiated now, and its linkage might have changed.
+          Consumer.HandleTopLevelDecl(DeclGroupRef(Function));
+        } else if (TSK == TSK_ExplicitInstantiationDefinition) {
           InstantiateFunctionDefinition(PointOfInstantiation, Function);
-        } else {
-          Function->setTemplateSpecializationKind(TSK, PointOfInstantiation);
-          if (TSK == TSK_ImplicitInstantiation)
-            PendingLocalImplicitInstantiations.push_back(
-                std::make_pair(Function, PointOfInstantiation));
+        } else if (TSK == TSK_ImplicitInstantiation) {
+          PendingLocalImplicitInstantiations.push_back(
+              std::make_pair(Function, PointOfInstantiation));
         }
       }
     } else if (auto *Var = dyn_cast<VarDecl>(D)) {
@@ -2682,7 +2685,7 @@
       if (const TagDecl *Tag = dyn_cast<TagDecl>(CheckD))
         CheckD = Tag->getPreviousDecl();
       else
-        CheckD = 0;
+        CheckD = nullptr;
     } while (CheckD);
     
     // If we aren't combined with our outer scope, we're done. 
@@ -2694,13 +2697,13 @@
   // deduction, we may not have values for template parameters yet.
   if (isa<NonTypeTemplateParmDecl>(D) || isa<TemplateTypeParmDecl>(D) ||
       isa<TemplateTemplateParmDecl>(D))
-    return 0;
+    return nullptr;
 
   // If we didn't find the decl, then we either have a sema bug, or we have a
   // forward reference to a label declaration.  Return null to indicate that
   // we have an uninstantiated label.
   assert(isa<LabelDecl>(D) && "declaration not instantiated in this scope");
-  return 0;
+  return nullptr;
 }
 
 void LocalInstantiationScope::InstantiatedLocal(const Decl *D, Decl *Inst) {
@@ -2747,7 +2750,7 @@
                                          const TemplateArgument **ExplicitArgs,
                                               unsigned *NumExplicitArgs) const {
   if (ExplicitArgs)
-    *ExplicitArgs = 0;
+    *ExplicitArgs = nullptr;
   if (NumExplicitArgs)
     *NumExplicitArgs = 0;
   
@@ -2765,6 +2768,6 @@
     if (!Current->CombineWithOuterScope)
       break;
   }
-  
-  return 0;
+
+  return nullptr;
 }