3 files changed, 41 insertions, 2 deletions
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index e9d8c0f304c..94038418df1 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -2216,6 +2216,32 @@ ASTContext::getDependentTemplateSpecializationType(
   return QualType(T, 0);
 }
 
+QualType ASTContext::getPackExpansionType(QualType Pattern) {
+  llvm::FoldingSetNodeID ID;
+  PackExpansionType::Profile(ID, Pattern);
+
+  assert(Pattern->containsUnexpandedParameterPack() &&
+         "Pack expansions must expand one or more parameter packs");
+  void *InsertPos = 0;
+  PackExpansionType *T
+    = PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
+  if (T)
+    return QualType(T, 0);
+
+  QualType Canon;
+  if (!Pattern.isCanonical()) {
+    Canon = getPackExpansionType(getCanonicalType(Pattern));
+
+    // Find the insert position again.
+    PackExpansionTypes.FindNodeOrInsertPos(ID, InsertPos);
+  }
+
+  T = new (*this) PackExpansionType(Pattern, Canon);
+  Types.push_back(T);
+  PackExpansionTypes.InsertNode(T, InsertPos);
+  return QualType(T, 0);  
+}
+
 /// CmpProtocolNames - Comparison predicate for sorting protocols
 /// alphabetically.
 static bool CmpProtocolNames(const ObjCProtocolDecl *LHS,
diff --git a/clang/lib/AST/ASTImporter.cpp b/clang/lib/AST/ASTImporter.cpp
index cc485c47d9f..7ff217e3345 100644
--- a/clang/lib/AST/ASTImporter.cpp
+++ b/clang/lib/AST/ASTImporter.cpp
@@ -707,7 +707,14 @@ static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
     }
     break;
   }
-  
+
+  case Type::PackExpansion:
+    if (!IsStructurallyEquivalent(Context,
+                                  cast<PackExpansionType>(T1)->getPattern(),
+                                  cast<PackExpansionType>(T2)->getPattern()))
+      return false;
+    break;
+
   case Type::ObjCInterface: {
     const ObjCInterfaceType *Iface1 = cast<ObjCInterfaceType>(T1);
     const ObjCInterfaceType *Iface2 = cast<ObjCInterfaceType>(T2);
diff --git a/clang/lib/AST/TypePrinter.cpp b/clang/lib/AST/TypePrinter.cpp
index 15c3fb2fbf2..e12d7e0185d 100644
--- a/clang/lib/AST/TypePrinter.cpp
+++ b/clang/lib/AST/TypePrinter.cpp
@@ -36,7 +36,7 @@ namespace {
     void printTag(TagDecl *T, std::string &S);
 #define ABSTRACT_TYPE(CLASS, PARENT)
 #define TYPE(CLASS, PARENT) \
-  void print##CLASS(const CLASS##Type *T, std::string &S);
+    void print##CLASS(const CLASS##Type *T, std::string &S);
 #include "clang/AST/TypeNodes.def"
   };
 }
@@ -668,6 +668,12 @@ void TypePrinter::printDependentTemplateSpecialization(
     S = MyString + ' ' + S;
 }
 
+void TypePrinter::printPackExpansion(const PackExpansionType *T, 
+                                     std::string &S) {
+  print(T->getPattern(), S);
+  S += "...";
+}
+
 void TypePrinter::printObjCInterface(const ObjCInterfaceType *T, 
                                      std::string &S) { 
   if (!S.empty())    // Prefix the basic type, e.g. 'typedefname X'.