4 files changed, 57 insertions, 2 deletions
diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index 65474348834..f39055fd873 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -764,7 +764,7 @@ llvm::DIType CGDebugInfo::getOrCreateType(QualType Ty,
 #define DEPENDENT_TYPE(Class, Base) case Type::Class:
 #include "clang/AST/TypeNodes.def"
     assert(false && "Dependent types cannot show up in debug information");
-    
+
   case Type::LValueReference:
   case Type::RValueReference:
   case Type::Vector:
diff --git a/clang/lib/Sema/Sema.h b/clang/lib/Sema/Sema.h
index b93faff7a02..35a2ae6741a 100644
--- a/clang/lib/Sema/Sema.h
+++ b/clang/lib/Sema/Sema.h
@@ -128,6 +128,40 @@ struct BlockSemaInfo {
   BlockSemaInfo *PrevBlockInfo;
 };
 
+/// \brief Holds a QualType and a DeclaratorInfo* that came out of a declarator
+/// parsing.
+///
+/// LocInfoType is a "transient" type, only needed for passing to/from Parser
+/// and Sema, when we want to preserve type source info for a parsed type.
+/// It will not participate in the type system semantics in any way.
+class LocInfoType : public Type {
+  enum {
+    // The last number that can fit in Type's TC.
+    // Avoids conflict with an existing Type class. 
+    LocInfo = (1 << TypeClassBitSize) - 1
+  };
+
+  DeclaratorInfo *DeclInfo;
+
+  LocInfoType(QualType ty, DeclaratorInfo *DInfo)
+    : Type((TypeClass)LocInfo, ty, ty->isDependentType()), DeclInfo(DInfo) {
+    assert(getTypeClass() == (TypeClass)LocInfo && "LocInfo didn't fit in TC?");
+  }
+  friend class Sema;
+
+public:
+  QualType getType() const { return getCanonicalTypeInternal(); }
+  DeclaratorInfo *getDeclaratorInfo() const { return DeclInfo; }
+
+  virtual void getAsStringInternal(std::string &Str,
+                                   const PrintingPolicy &Policy) const;
+
+  static bool classof(const Type *T) {
+    return T->getTypeClass() == (TypeClass)LocInfo;
+  }
+  static bool classof(const LocInfoType *) { return true; }
+};
+
 /// Sema - This implements semantic analysis and AST building for C.
 class Sema : public Action {
   Sema(const Sema&);           // DO NOT IMPLEMENT
@@ -301,6 +335,8 @@ public:
   /// unit.
   bool CompleteTranslationUnit;
 
+  llvm::BumpPtrAllocator BumpAlloc;
+
   /// \brief The number of SFINAE diagnostics that have been trapped.
   unsigned NumSFINAEErrors;
 
@@ -425,6 +461,8 @@ public:
                                 unsigned Skip = 0, TagDecl **OwnedDecl = 0);
   DeclaratorInfo *GetDeclaratorInfoForDeclarator(Declarator &D, QualType T,
                                                  unsigned Skip);
+  /// \brief Create a LocInfoType to hold the given QualType and DeclaratorInfo.
+  QualType CreateLocInfoType(QualType T, DeclaratorInfo *DInfo);
   DeclarationName GetNameForDeclarator(Declarator &D);
   bool CheckSpecifiedExceptionType(QualType T, const SourceRange &Range);
   bool CheckDistantExceptionSpec(QualType T);
diff --git a/clang/lib/Sema/SemaType.cpp b/clang/lib/Sema/SemaType.cpp
index 03735bae406..0890340fe9c 100644
--- a/clang/lib/Sema/SemaType.cpp
+++ b/clang/lib/Sema/SemaType.cpp
@@ -1309,6 +1309,23 @@ Sema::GetDeclaratorInfoForDeclarator(Declarator &D, QualType T, unsigned Skip) {
   return DInfo;
 }
 
+/// \brief Create a LocInfoType to hold the given QualType and DeclaratorInfo.
+QualType Sema::CreateLocInfoType(QualType T, DeclaratorInfo *DInfo) {
+  // FIXME: LocInfoTypes are "transient", only needed for passing to/from Parser
+  // and Sema during declaration parsing. Try deallocating/caching them when
+  // it's appropriate, instead of allocating them and keeping them around.
+  LocInfoType *LocT = (LocInfoType*)BumpAlloc.Allocate(sizeof(LocInfoType), 8);
+  new (LocT) LocInfoType(T, DInfo);
+  assert(LocT->getTypeClass() != T->getTypeClass() &&
+         "LocInfoType's TypeClass conflicts with an existing Type class");
+  return QualType(LocT, 0);
+}
+
+void LocInfoType::getAsStringInternal(std::string &Str,
+                                      const PrintingPolicy &Policy) const {
+  assert(false && "LocInfoType should not be used in the type system");
+}
+
 /// CheckSpecifiedExceptionType - Check if the given type is valid in an
 /// exception specification. Incomplete types, or pointers to incomplete types
 /// other than void are not allowed.
diff --git a/clang/lib/Sema/TreeTransform.h b/clang/lib/Sema/TreeTransform.h
index 5516ab44106..e734d07e857 100644
--- a/clang/lib/Sema/TreeTransform.h
+++ b/clang/lib/Sema/TreeTransform.h
@@ -1561,7 +1561,7 @@ TreeTransform<Derived>::AddTypeQualifiers(QualType T, unsigned CVRQualifiers) {
   
   return T;
 }
-  
+
 template<typename Derived> 
 QualType TreeTransform<Derived>::TransformExtQualType(const ExtQualType *T) { 
   // FIXME: Implement