1 files changed, 116 insertions, 98 deletions

diff --git a/include/clang/AST/ExprCXX.h b/include/clang/AST/ExprCXX.h
index ecfa9e213637..9c759db1f97a 100644
--- a/include/clang/AST/ExprCXX.h
+++ b/include/clang/AST/ExprCXX.h
@@ -53,14 +53,19 @@ class CXXOperatorCallExpr : public CallExpr {
   OverloadedOperatorKind Operator;
   SourceRange Range;
 
+  // Record the FP_CONTRACT state that applies to this operator call. Only
+  // meaningful for floating point types. For other types this value can be
+  // set to false.
+  unsigned FPContractable : 1;
+
   SourceRange getSourceRangeImpl() const LLVM_READONLY;
 public:
   CXXOperatorCallExpr(ASTContext& C, OverloadedOperatorKind Op, Expr *fn,
-                      Expr **args, unsigned numargs, QualType t,
-                      ExprValueKind VK, SourceLocation operatorloc)
-    : CallExpr(C, CXXOperatorCallExprClass, fn, 0, args, numargs, t, VK,
+                      ArrayRef<Expr*> args, QualType t, ExprValueKind VK,
+                      SourceLocation operatorloc, bool fpContractable)
+    : CallExpr(C, CXXOperatorCallExprClass, fn, 0, args, t, VK,
                operatorloc),
-      Operator(Op) {
+      Operator(Op), FPContractable(fpContractable) {
     Range = getSourceRangeImpl();
   }
   explicit CXXOperatorCallExpr(ASTContext& C, EmptyShell Empty) :
@@ -83,7 +88,14 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXOperatorCallExprClass;
   }
-  static bool classof(const CXXOperatorCallExpr *) { return true; }
+
+  // Set the FP contractability status of this operator. Only meaningful for
+  // operations on floating point types.
+  void setFPContractable(bool FPC) { FPContractable = FPC; }
+
+  // Get the FP contractability status of this operator. Only meaningful for
+  // operations on floating point types.
+  bool isFPContractable() const { return FPContractable; }
 
   friend class ASTStmtReader;
   friend class ASTStmtWriter;
@@ -99,9 +111,9 @@ public:
 /// the object argument).
 class CXXMemberCallExpr : public CallExpr {
 public:
-  CXXMemberCallExpr(ASTContext &C, Expr *fn, Expr **args, unsigned numargs,
+  CXXMemberCallExpr(ASTContext &C, Expr *fn, ArrayRef<Expr*> args,
                     QualType t, ExprValueKind VK, SourceLocation RP)
-    : CallExpr(C, CXXMemberCallExprClass, fn, 0, args, numargs, t, VK, RP) {}
+    : CallExpr(C, CXXMemberCallExprClass, fn, 0, args, t, VK, RP) {}
 
   CXXMemberCallExpr(ASTContext &C, EmptyShell Empty)
     : CallExpr(C, CXXMemberCallExprClass, Empty) { }
@@ -124,7 +136,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXMemberCallExprClass;
   }
-  static bool classof(const CXXMemberCallExpr *) { return true; }
 };
 
 /// CUDAKernelCallExpr - Represents a call to a CUDA kernel function.
@@ -134,10 +145,9 @@ private:
 
 public:
   CUDAKernelCallExpr(ASTContext &C, Expr *fn, CallExpr *Config,
-                     Expr **args, unsigned numargs, QualType t,
-                     ExprValueKind VK, SourceLocation RP)
-    : CallExpr(C, CUDAKernelCallExprClass, fn, END_PREARG, args, numargs, t, VK,
-               RP) {
+                     ArrayRef<Expr*> args, QualType t, ExprValueKind VK,
+                     SourceLocation RP)
+    : CallExpr(C, CUDAKernelCallExprClass, fn, END_PREARG, args, t, VK, RP) {
     setConfig(Config);
   }
 
@@ -153,7 +163,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CUDAKernelCallExprClass;
   }
-  static bool classof(const CUDAKernelCallExpr *) { return true; }
 };
 
 /// CXXNamedCastExpr - Abstract class common to all of the C++ "named"
@@ -205,7 +214,6 @@ public:
       return false;
     }
   }
-  static bool classof(const CXXNamedCastExpr *) { return true; }
 };
 
 /// CXXStaticCastExpr - A C++ @c static_cast expression
@@ -235,7 +243,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXStaticCastExprClass;
   }
-  static bool classof(const CXXStaticCastExpr *) { return true; }
 };
 
 /// CXXDynamicCastExpr - A C++ @c dynamic_cast expression
@@ -269,7 +276,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXDynamicCastExprClass;
   }
-  static bool classof(const CXXDynamicCastExpr *) { return true; }
 };
 
 /// CXXReinterpretCastExpr - A C++ @c reinterpret_cast expression (C++
@@ -301,7 +307,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXReinterpretCastExprClass;
   }
-  static bool classof(const CXXReinterpretCastExpr *) { return true; }
 };
 
 /// CXXConstCastExpr - A C++ @c const_cast expression (C++ [expr.const.cast]),
@@ -329,7 +334,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXConstCastExprClass;
   }
-  static bool classof(const CXXConstCastExpr *) { return true; }
 };
 
 /// UserDefinedLiteral - A call to a literal operator (C++11 [over.literal])
@@ -346,11 +350,11 @@ class UserDefinedLiteral : public CallExpr {
   SourceLocation UDSuffixLoc;
 
 public:
-  UserDefinedLiteral(ASTContext &C, Expr *Fn, Expr **Args, unsigned NumArgs,
+  UserDefinedLiteral(ASTContext &C, Expr *Fn, ArrayRef<Expr*> Args,
                      QualType T, ExprValueKind VK, SourceLocation LitEndLoc,
                      SourceLocation SuffixLoc)
-    : CallExpr(C, UserDefinedLiteralClass, Fn, 0, Args, NumArgs, T, VK,
-               LitEndLoc), UDSuffixLoc(SuffixLoc) {}
+    : CallExpr(C, UserDefinedLiteralClass, Fn, 0, Args, T, VK, LitEndLoc),
+      UDSuffixLoc(SuffixLoc) {}
   explicit UserDefinedLiteral(ASTContext &C, EmptyShell Empty)
     : CallExpr(C, UserDefinedLiteralClass, Empty) {}
 
@@ -398,7 +402,6 @@ public:
   static bool classof(const Stmt *S) {
     return S->getStmtClass() == UserDefinedLiteralClass;
   }
-  static bool classof(const UserDefinedLiteral *) { return true; }
 
   friend class ASTStmtReader;
   friend class ASTStmtWriter;
@@ -429,7 +432,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXBoolLiteralExprClass;
   }
-  static bool classof(const CXXBoolLiteralExpr *) { return true; }
 
   // Iterators
   child_range children() { return child_range(); }
@@ -455,7 +457,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXNullPtrLiteralExprClass;
   }
-  static bool classof(const CXXNullPtrLiteralExpr *) { return true; }
 
   child_range children() { return child_range(); }
 };
@@ -536,7 +537,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXTypeidExprClass;
   }
-  static bool classof(const CXXTypeidExpr *) { return true; }
 
   // Iterators
   child_range children() {
@@ -611,7 +611,9 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXUuidofExprClass;
   }
-  static bool classof(const CXXUuidofExpr *) { return true; }
+
+  /// Grabs __declspec(uuid()) off a type, or returns 0 if there is none.
+  static UuidAttr *GetUuidAttrOfType(QualType QT);
 
   // Iterators
   child_range children() {
@@ -659,7 +661,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXThisExprClass;
   }
-  static bool classof(const CXXThisExpr *) { return true; }
 
   // Iterators
   child_range children() { return child_range(); }
@@ -710,7 +711,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXThrowExprClass;
   }
-  static bool classof(const CXXThrowExpr *) { return true; }
 
   // Iterators
   child_range children() {
@@ -798,7 +798,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXDefaultArgExprClass;
   }
-  static bool classof(const CXXDefaultArgExpr *) { return true; }
 
   // Iterators
   child_range children() { return child_range(); }
@@ -875,7 +874,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXBindTemporaryExprClass;
   }
-  static bool classof(const CXXBindTemporaryExpr *) { return true; }
 
   // Iterators
   child_range children() { return child_range(&SubExpr, &SubExpr + 1); }
@@ -908,7 +906,7 @@ protected:
   CXXConstructExpr(ASTContext &C, StmtClass SC, QualType T,
                    SourceLocation Loc,
                    CXXConstructorDecl *d, bool elidable,
-                   Expr **args, unsigned numargs,
+                   ArrayRef<Expr *> Args,
                    bool HadMultipleCandidates,
                    bool ListInitialization,
                    bool ZeroInitialization,
@@ -934,7 +932,7 @@ public:
   static CXXConstructExpr *Create(ASTContext &C, QualType T,
                                   SourceLocation Loc,
                                   CXXConstructorDecl *D, bool Elidable,
-                                  Expr **Args, unsigned NumArgs,
+                                  ArrayRef<Expr *> Args,
                                   bool HadMultipleCandidates,
                                   bool ListInitialization,
                                   bool ZeroInitialization,
@@ -1011,7 +1009,6 @@ public:
     return T->getStmtClass() == CXXConstructExprClass ||
       T->getStmtClass() == CXXTemporaryObjectExprClass;
   }
-  static bool classof(const CXXConstructExpr *) { return true; }
 
   // Iterators
   child_range children() {
@@ -1066,7 +1063,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXFunctionalCastExprClass;
   }
-  static bool classof(const CXXFunctionalCastExpr *) { return true; }
 };
 
 /// @brief Represents a C++ functional cast expression that builds a
@@ -1090,7 +1086,7 @@ class CXXTemporaryObjectExpr : public CXXConstructExpr {
 public:
   CXXTemporaryObjectExpr(ASTContext &C, CXXConstructorDecl *Cons,
                          TypeSourceInfo *Type,
-                         Expr **Args,unsigned NumArgs,
+                         ArrayRef<Expr *> Args,
                          SourceRange parenRange,
                          bool HadMultipleCandidates,
                          bool ZeroInitialization = false);
@@ -1104,7 +1100,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXTemporaryObjectExprClass;
   }
-  static bool classof(const CXXTemporaryObjectExpr *) { return true; }
 
   friend class ASTStmtReader;
 };
@@ -1281,8 +1276,11 @@ private:
   
   /// \brief Retrieve the complete set of array-index variables.
   VarDecl **getArrayIndexVars() const {
+    unsigned ArrayIndexSize =
+        llvm::RoundUpToAlignment(sizeof(unsigned) * (NumCaptures + 1),
+                                 llvm::alignOf<VarDecl*>());
     return reinterpret_cast<VarDecl **>(
-             getArrayIndexStarts() + NumCaptures + 1);
+        reinterpret_cast<char*>(getArrayIndexStarts()) + ArrayIndexSize);
   }
 
 public:
@@ -1394,7 +1392,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == LambdaExprClass;
   }
-  static bool classof(const LambdaExpr *) { return true; }
 
   SourceRange getSourceRange() const LLVM_READONLY {
     return SourceRange(IntroducerRange.getBegin(), ClosingBrace);
@@ -1442,7 +1439,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXScalarValueInitExprClass;
   }
-  static bool classof(const CXXScalarValueInitExpr *) { return true; }
 
   // Iterators
   child_range children() { return child_range(); }
@@ -1467,8 +1463,8 @@ class CXXNewExpr : public Expr {
   /// the source range covering the parenthesized type-id.
   SourceRange TypeIdParens;
 
-  /// \brief Location of the first token.
-  SourceLocation StartLoc;
+  /// \brief Range of the entire new expression.
+  SourceRange Range;
 
   /// \brief Source-range of a paren-delimited initializer.
   SourceRange DirectInitRange;
@@ -1498,11 +1494,11 @@ public:
 
   CXXNewExpr(ASTContext &C, bool globalNew, FunctionDecl *operatorNew,
              FunctionDecl *operatorDelete, bool usualArrayDeleteWantsSize,
-             Expr **placementArgs, unsigned numPlaceArgs,
+             ArrayRef<Expr*> placementArgs,
              SourceRange typeIdParens, Expr *arraySize,
              InitializationStyle initializationStyle, Expr *initializer,
              QualType ty, TypeSourceInfo *AllocatedTypeInfo,
-             SourceLocation startLoc, SourceRange directInitRange);
+             SourceRange Range, SourceRange directInitRange);
   explicit CXXNewExpr(EmptyShell Shell)
     : Expr(CXXNewExprClass, Shell), SubExprs(0) { }
 
@@ -1580,7 +1576,7 @@ public:
   }
 
   /// \brief Returns the CXXConstructExpr from this new-expression, or NULL.
-  const CXXConstructExpr* getConstructExpr() {
+  const CXXConstructExpr* getConstructExpr() const {
     return dyn_cast_or_null<CXXConstructExpr>(getInitializer());
   }
 
@@ -1617,19 +1613,18 @@ public:
     return SubExprs + Array + hasInitializer() + getNumPlacementArgs();
   }
 
-  SourceLocation getStartLoc() const { return StartLoc; }
-  SourceLocation getEndLoc() const;
+  SourceLocation getStartLoc() const { return Range.getBegin(); }
+  SourceLocation getEndLoc() const { return Range.getEnd(); }
 
   SourceRange getDirectInitRange() const { return DirectInitRange; }
 
   SourceRange getSourceRange() const LLVM_READONLY {
-    return SourceRange(getStartLoc(), getEndLoc());
+    return Range;
   }
 
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXNewExprClass;
   }
-  static bool classof(const CXXNewExpr *) { return true; }
 
   // Iterators
   child_range children() {
@@ -1700,7 +1695,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXDeleteExprClass;
   }
-  static bool classof(const CXXDeleteExpr *) { return true; }
 
   // Iterators
   child_range children() { return child_range(&Argument, &Argument+1); }
@@ -1889,7 +1883,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXPseudoDestructorExprClass;
   }
-  static bool classof(const CXXPseudoDestructorExpr *) { return true; }
 
   // Iterators
   child_range children() { return child_range(&Base, &Base + 1); }
@@ -1945,7 +1938,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == UnaryTypeTraitExprClass;
   }
-  static bool classof(const UnaryTypeTraitExpr *) { return true; }
 
   // Iterators
   child_range children() { return child_range(); }
@@ -2017,7 +2009,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == BinaryTypeTraitExprClass;
   }
-  static bool classof(const BinaryTypeTraitExpr *) { return true; }
 
   // Iterators
   child_range children() { return child_range(); }
@@ -2111,7 +2102,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == TypeTraitExprClass;
   }
-  static bool classof(const TypeTraitExpr *) { return true; }
   
   // Iterators
   child_range children() { return child_range(); }
@@ -2186,7 +2176,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == ArrayTypeTraitExprClass;
   }
-  static bool classof(const ArrayTypeTraitExpr *) { return true; }
 
   // Iterators
   child_range children() { return child_range(); }
@@ -2245,7 +2234,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == ExpressionTraitExprClass;
   }
-  static bool classof(const ExpressionTraitExpr *) { return true; }
 
   // Iterators
   child_range children() { return child_range(); }
@@ -2432,7 +2420,6 @@ public:
     return T->getStmtClass() == UnresolvedLookupExprClass ||
            T->getStmtClass() == UnresolvedMemberExprClass;
   }
-  static bool classof(const OverloadExpr *) { return true; }
 
   friend class ASTStmtReader;
   friend class ASTStmtWriter;
@@ -2454,10 +2441,6 @@ class UnresolvedLookupExpr : public OverloadExpr {
   /// call.
   bool RequiresADL;
 
-  /// True if namespace ::std should be considered an associated namespace
-  /// for the purposes of argument-dependent lookup. See C++0x [stmt.ranged]p1.
-  bool StdIsAssociatedNamespace;
-
   /// True if these lookup results are overloaded.  This is pretty
   /// trivially rederivable if we urgently need to kill this field.
   bool Overloaded;
@@ -2476,19 +2459,16 @@ class UnresolvedLookupExpr : public OverloadExpr {
                        const DeclarationNameInfo &NameInfo,
                        bool RequiresADL, bool Overloaded,
                        const TemplateArgumentListInfo *TemplateArgs,
-                       UnresolvedSetIterator Begin, UnresolvedSetIterator End,
-                       bool StdIsAssociatedNamespace)
+                       UnresolvedSetIterator Begin, UnresolvedSetIterator End)
     : OverloadExpr(UnresolvedLookupExprClass, C, QualifierLoc, TemplateKWLoc,
                    NameInfo, TemplateArgs, Begin, End, false, false, false),
       RequiresADL(RequiresADL),
-      StdIsAssociatedNamespace(StdIsAssociatedNamespace),
       Overloaded(Overloaded), NamingClass(NamingClass)
   {}
 
   UnresolvedLookupExpr(EmptyShell Empty)
     : OverloadExpr(UnresolvedLookupExprClass, Empty),
-      RequiresADL(false), StdIsAssociatedNamespace(false), Overloaded(false),
-      NamingClass(0)
+      RequiresADL(false), Overloaded(false), NamingClass(0)
   {}
 
   friend class ASTStmtReader;
@@ -2500,14 +2480,10 @@ public:
                                       const DeclarationNameInfo &NameInfo,
                                       bool ADL, bool Overloaded,
                                       UnresolvedSetIterator Begin,
-                                      UnresolvedSetIterator End,
-                                      bool StdIsAssociatedNamespace = false) {
-    assert((ADL || !StdIsAssociatedNamespace) &&
-           "std considered associated namespace when not performing ADL");
+                                      UnresolvedSetIterator End) {
     return new(C) UnresolvedLookupExpr(C, NamingClass, QualifierLoc,
                                        SourceLocation(), NameInfo,
-                                       ADL, Overloaded, 0, Begin, End,
-                                       StdIsAssociatedNamespace);
+                                       ADL, Overloaded, 0, Begin, End);
   }
 
   static UnresolvedLookupExpr *Create(ASTContext &C,
@@ -2528,10 +2504,6 @@ public:
   /// argument-dependent lookup.
   bool requiresADL() const { return RequiresADL; }
 
-  /// True if namespace \::std should be artificially added to the set of
-  /// associated namespaces for argument-dependent lookup purposes.
-  bool isStdAssociatedNamespace() const { return StdIsAssociatedNamespace; }
-
   /// True if this lookup is overloaded.
   bool isOverloaded() const { return Overloaded; }
 
@@ -2554,7 +2526,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == UnresolvedLookupExprClass;
   }
-  static bool classof(const UnresolvedLookupExpr *) { return true; }
 };
 
 /// \brief A qualified reference to a name whose declaration cannot
@@ -2705,7 +2676,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == DependentScopeDeclRefExprClass;
   }
-  static bool classof(const DependentScopeDeclRefExpr *) { return true; }
 
   child_range children() { return child_range(); }
 
@@ -2778,7 +2748,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == ExprWithCleanupsClass;
   }
-  static bool classof(const ExprWithCleanups *) { return true; }
 
   // Iterators
   child_range children() { return child_range(&SubExpr, &SubExpr + 1); }
@@ -2820,8 +2789,7 @@ class CXXUnresolvedConstructExpr : public Expr {
 
   CXXUnresolvedConstructExpr(TypeSourceInfo *Type,
                              SourceLocation LParenLoc,
-                             Expr **Args,
-                             unsigned NumArgs,
+                             ArrayRef<Expr*> Args,
                              SourceLocation RParenLoc);
 
   CXXUnresolvedConstructExpr(EmptyShell Empty, unsigned NumArgs)
@@ -2833,8 +2801,7 @@ public:
   static CXXUnresolvedConstructExpr *Create(ASTContext &C,
                                             TypeSourceInfo *Type,
                                             SourceLocation LParenLoc,
-                                            Expr **Args,
-                                            unsigned NumArgs,
+                                            ArrayRef<Expr*> Args,
                                             SourceLocation RParenLoc);
 
   static CXXUnresolvedConstructExpr *CreateEmpty(ASTContext &C,
@@ -2893,7 +2860,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXUnresolvedConstructExprClass;
   }
-  static bool classof(const CXXUnresolvedConstructExpr *) { return true; }
 
   // Iterators
   child_range children() {
@@ -3142,7 +3108,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXDependentScopeMemberExprClass;
   }
-  static bool classof(const CXXDependentScopeMemberExpr *) { return true; }
 
   // Iterators
   child_range children() {
@@ -3276,7 +3241,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == UnresolvedMemberExprClass;
   }
-  static bool classof(const UnresolvedMemberExpr *) { return true; }
 
   // Iterators
   child_range children() {
@@ -3320,7 +3284,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXNoexceptExprClass;
   }
-  static bool classof(const CXXNoexceptExpr *) { return true; }
 
   // Iterators
   child_range children() { return child_range(&Operand, &Operand + 1); }
@@ -3397,7 +3360,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == PackExpansionExprClass;
   }
-  static bool classof(const PackExpansionExpr *) { return true; }
 
   // Iterators
   child_range children() {
@@ -3503,7 +3465,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == SizeOfPackExprClass;
   }
-  static bool classof(const SizeOfPackExpr *) { return true; }
 
   // Iterators
   child_range children() { return child_range(); }
@@ -3548,9 +3509,6 @@ public:
   static bool classof(const Stmt *s) {
     return s->getStmtClass() == SubstNonTypeTemplateParmExprClass;
   }
-  static bool classof(const SubstNonTypeTemplateParmExpr *) {
-    return true;
-  }
 
   // Iterators
   child_range children() { return child_range(&Replacement, &Replacement+1); }
@@ -3561,7 +3519,7 @@ public:
 ///
 /// When a pack expansion in the source code contains multiple parameter packs
 /// and those parameter packs correspond to different levels of template
-/// parameter lists, this node node is used to represent a non-type template
+/// parameter lists, this node is used to represent a non-type template
 /// parameter pack from an outer level, which has already had its argument pack
 /// substituted but that still lives within a pack expansion that itself
 /// could not be instantiated. When actually performing a substitution into
@@ -3608,14 +3566,77 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == SubstNonTypeTemplateParmPackExprClass;
   }
-  static bool classof(const SubstNonTypeTemplateParmPackExpr *) {
-    return true;
-  }
 
   // Iterators
   child_range children() { return child_range(); }
 };
 
+/// \brief Represents a reference to a function parameter pack that has been
+/// substituted but not yet expanded.
+///
+/// When a pack expansion contains multiple parameter packs at different levels,
+/// this node is used to represent a function parameter pack at an outer level
+/// which we have already substituted to refer to expanded parameters, but where
+/// the containing pack expansion cannot yet be expanded.
+///
+/// \code
+/// template<typename...Ts> struct S {
+///   template<typename...Us> auto f(Ts ...ts) -> decltype(g(Us(ts)...));
+/// };
+/// template struct S<int, int>;
+/// \endcode
+class FunctionParmPackExpr : public Expr {
+  /// \brief The function parameter pack which was referenced.
+  ParmVarDecl *ParamPack;
+
+  /// \brief The location of the function parameter pack reference.
+  SourceLocation NameLoc;
+
+  /// \brief The number of expansions of this pack.
+  unsigned NumParameters;
+
+  FunctionParmPackExpr(QualType T, ParmVarDecl *ParamPack,
+                       SourceLocation NameLoc, unsigned NumParams,
+                       Decl * const *Params);
+
+  friend class ASTReader;
+  friend class ASTStmtReader;
+
+public:
+  static FunctionParmPackExpr *Create(ASTContext &Context, QualType T,
+                                      ParmVarDecl *ParamPack,
+                                      SourceLocation NameLoc,
+                                      llvm::ArrayRef<Decl*> Params);
+  static FunctionParmPackExpr *CreateEmpty(ASTContext &Context,
+                                           unsigned NumParams);
+
+  /// \brief Get the parameter pack which this expression refers to.
+  ParmVarDecl *getParameterPack() const { return ParamPack; }
+
+  /// \brief Get the location of the parameter pack.
+  SourceLocation getParameterPackLocation() const { return NameLoc; }
+
+  /// \brief Iterators over the parameters which the parameter pack expanded
+  /// into.
+  typedef ParmVarDecl * const *iterator;
+  iterator begin() const { return reinterpret_cast<iterator>(this+1); }
+  iterator end() const { return begin() + NumParameters; }
+
+  /// \brief Get the number of parameters in this parameter pack.
+  unsigned getNumExpansions() const { return NumParameters; }
+
+  /// \brief Get an expansion of the parameter pack by index.
+  ParmVarDecl *getExpansion(unsigned I) const { return begin()[I]; }
+
+  SourceRange getSourceRange() const LLVM_READONLY { return NameLoc; }
+
+  static bool classof(const Stmt *T) {
+    return T->getStmtClass() == FunctionParmPackExprClass;
+  }
+
+  child_range children() { return child_range(); }
+};
+
 /// \brief Represents a prvalue temporary that written into memory so that
 /// a reference can bind to it.
 ///
@@ -3670,9 +3691,6 @@ public:
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == MaterializeTemporaryExprClass;
   }
-  static bool classof(const MaterializeTemporaryExpr *) {
-    return true;
-  }
 
   // Iterators
   child_range children() { return child_range(&Temporary, &Temporary + 1); }