From: Sebastian Redl <sebastian.redl@getdesigned.at>
Date: Sun, 15 Mar 2009 17:47:39 +0000 (+0000)
Subject: Convert a bunch of actions to smart pointers, and also bring PrintParserCallbacks... 
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=f53597fb16142bdb4a66901f8c0b768db4f2a548;p=clang

Convert a bunch of actions to smart pointers, and also bring PrintParserCallbacks a bit more in line with reality.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@67029 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/Driver/PrintParserCallbacks.cpp b/Driver/PrintParserCallbacks.cpp
index 760037806a..f9399e2e1e 100644
--- a/Driver/PrintParserCallbacks.cpp
+++ b/Driver/PrintParserCallbacks.cpp
@@ -584,58 +584,235 @@ namespace {
 
     //===--------------------- GNU Extension Expressions ------------------===//
 
-    virtual ExprResult ActOnAddrLabel(SourceLocation OpLoc, SourceLocation LabLoc,
-                                      IdentifierInfo *LabelII) { // "&&foo"
+    virtual OwningExprResult ActOnAddrLabel(SourceLocation OpLoc,
+                                            SourceLocation LabLoc,
+                                            IdentifierInfo *LabelII) {// "&&foo"
       llvm::cout << __FUNCTION__ << "\n";
-      return 0;
+      return ExprEmpty();
     }
-  
-    virtual ExprResult ActOnStmtExpr(SourceLocation LPLoc, StmtTy *SubStmt,
-                                     SourceLocation RPLoc) { // "({..})"
+
+    virtual OwningExprResult ActOnStmtExpr(SourceLocation LPLoc,
+                                           StmtArg SubStmt,
+                                           SourceLocation RPLoc) { // "({..})"
       llvm::cout << __FUNCTION__ << "\n";
-      return 0;
+      return ExprEmpty();
     }
-  
-    virtual ExprResult ActOnBuiltinOffsetOf(Scope *S, SourceLocation BuiltinLoc,
-                                            SourceLocation TypeLoc, TypeTy *Arg1,
-                                            OffsetOfComponent *CompPtr,
-                                            unsigned NumComponents,
-                                            SourceLocation RParenLoc) {
+
+    virtual OwningExprResult ActOnBuiltinOffsetOf(Scope *S,
+                                                  SourceLocation BuiltinLoc,
+                                                  SourceLocation TypeLoc,
+                                                  TypeTy *Arg1,
+                                                  OffsetOfComponent *CompPtr,
+                                                  unsigned NumComponents,
+                                                  SourceLocation RParenLoc) {
       llvm::cout << __FUNCTION__ << "\n";
-      return 0;
+      return ExprEmpty();
     }
-  
+
     // __builtin_types_compatible_p(type1, type2)
-    virtual ExprResult ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 
-                                                TypeTy *arg1, TypeTy *arg2,
-                                                SourceLocation RPLoc) {
+    virtual OwningExprResult ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc,
+                                                      TypeTy *arg1,TypeTy *arg2,
+                                                      SourceLocation RPLoc) {
       llvm::cout << __FUNCTION__ << "\n";
-      return 0;
+      return ExprEmpty();
     }
     // __builtin_choose_expr(constExpr, expr1, expr2)
-    virtual ExprResult ActOnChooseExpr(SourceLocation BuiltinLoc, 
-                                       ExprTy *cond, ExprTy *expr1, ExprTy *expr2,
-                                       SourceLocation RPLoc) {
+    virtual OwningExprResult ActOnChooseExpr(SourceLocation BuiltinLoc,
+                                             ExprArg cond, ExprArg expr1,
+                                             ExprArg expr2,
+                                             SourceLocation RPLoc) {
+      llvm::cout << __FUNCTION__ << "\n";
+      return ExprEmpty();
+    }
+
+    // __builtin_va_arg(expr, type)
+    virtual OwningExprResult ActOnVAArg(SourceLocation BuiltinLoc,
+                                  ExprArg expr, TypeTy *type,
+                                  SourceLocation RPLoc) {
+      llvm::cout << __FUNCTION__ << "\n";
+      return ExprEmpty();
+    }
+
+    virtual OwningExprResult ActOnGNUNullExpr(SourceLocation TokenLoc) {
+      llvm::cout << __FUNCTION__ << "\n";
+      return ExprEmpty();
+    }
+
+    virtual void ActOnBlockStart(SourceLocation CaretLoc, Scope *CurScope) {
+      llvm::cout << __FUNCTION__ << "\n";
+    }
+
+    virtual void ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) {
+      llvm::cout << __FUNCTION__ << "\n";
+    }
+
+    virtual void ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) {
+      llvm::cout << __FUNCTION__ << "\n";
+    }
+
+    virtual OwningExprResult ActOnBlockStmtExpr(SourceLocation CaretLoc,
+                                                StmtArg Body,
+                                                Scope *CurScope) {
+      llvm::cout << __FUNCTION__ << "\n";
+      return ExprEmpty();
+    }
+
+    virtual DeclTy *ActOnStartNamespaceDef(Scope *S, SourceLocation IdentLoc,
+                                          IdentifierInfo *Ident,
+                                          SourceLocation LBrace) {
       llvm::cout << __FUNCTION__ << "\n";
       return 0;
     }
-    // __builtin_overload(...)
-    virtual ExprResult ActOnOverloadExpr(ExprTy **Args, unsigned NumArgs,
-                                         SourceLocation *CommaLocs,
-                                         SourceLocation BuiltinLoc, 
-                                         SourceLocation RPLoc) {
+
+    virtual void ActOnFinishNamespaceDef(DeclTy *Dcl,SourceLocation RBrace) {
+      llvm::cout << __FUNCTION__ << "\n";
+      return;
+    }
+
+#if 0
+    // FIXME: AttrList should be deleted by this function, but the definition
+    // would have to be available.
+    virtual DeclTy *ActOnUsingDirective(Scope *CurScope,
+                                        SourceLocation UsingLoc,
+                                        SourceLocation NamespcLoc,
+                                        const CXXScopeSpec &SS,
+                                        SourceLocation IdentLoc,
+                                        IdentifierInfo *NamespcName,
+                                        AttributeList *AttrList) {
       llvm::cout << __FUNCTION__ << "\n";
       return 0;
     }
-  
+#endif
 
-    // __builtin_va_arg(expr, type)
-    virtual ExprResult ActOnVAArg(SourceLocation BuiltinLoc,
-                                  ExprTy *expr, TypeTy *type,
-                                  SourceLocation RPLoc) {
+    virtual void ActOnParamDefaultArgument(DeclTy *param,
+                                           SourceLocation EqualLoc,
+                                           ExprArg defarg) {
+      llvm::cout << __FUNCTION__ << "\n";
+    }
+
+    virtual void ActOnParamUnparsedDefaultArgument(DeclTy *param,
+                                                   SourceLocation EqualLoc) {
+      llvm::cout << __FUNCTION__ << "\n";
+    }
+
+    virtual void ActOnParamDefaultArgumentError(DeclTy *param) {
+      llvm::cout << __FUNCTION__ << "\n";
+    }
+
+    virtual void AddCXXDirectInitializerToDecl(DeclTy *Dcl,
+                                               SourceLocation LParenLoc,
+                                               MultiExprArg Exprs,
+                                               SourceLocation *CommaLocs,
+                                               SourceLocation RParenLoc) {
+      llvm::cout << __FUNCTION__ << "\n";
+      return;
+    }
+
+    virtual void ActOnStartDelayedCXXMethodDeclaration(Scope *S, DeclTy *Method)
+    {
+      llvm::cout << __FUNCTION__ << "\n";
+    }
+
+    virtual void ActOnDelayedCXXMethodParameter(Scope *S, DeclTy *Param) {
+      llvm::cout << __FUNCTION__ << "\n";
+    }
+
+    virtual void ActOnFinishDelayedCXXMethodDeclaration(Scope *S,
+                                                        DeclTy *Method) {
+      llvm::cout << __FUNCTION__ << "\n";
+    }
+
+    virtual DeclTy *ActOnStaticAssertDeclaration(SourceLocation AssertLoc,
+                                                 ExprArg AssertExpr,
+                                                 ExprArg AssertMessageExpr,
+                                                 SourceLocation RParenLoc) {
       llvm::cout << __FUNCTION__ << "\n";
       return 0;
     }
+
+    virtual OwningExprResult ActOnCXXNamedCast(SourceLocation OpLoc,
+                                               tok::TokenKind Kind,
+                                               SourceLocation LAngleBracketLoc,
+                                               TypeTy *Ty,
+                                               SourceLocation RAngleBracketLoc,
+                                               SourceLocation LParenLoc,
+                                               ExprArg Op,
+                                               SourceLocation RParenLoc) {
+      llvm::cout << __FUNCTION__ << "\n";
+      return ExprEmpty();
+    }
+
+    virtual OwningExprResult ActOnCXXTypeid(SourceLocation OpLoc,
+                                            SourceLocation LParenLoc,
+                                            bool isType, void *TyOrExpr,
+                                            SourceLocation RParenLoc) {
+      llvm::cout << __FUNCTION__ << "\n";
+      return ExprEmpty();
+    }
+
+    virtual OwningExprResult ActOnCXXThis(SourceLocation ThisLoc) {
+      llvm::cout << __FUNCTION__ << "\n";
+      return ExprEmpty();
+    }
+
+    virtual OwningExprResult ActOnCXXBoolLiteral(SourceLocation OpLoc,
+                                                 tok::TokenKind Kind) {
+      llvm::cout << __FUNCTION__ << "\n";
+      return ExprEmpty();
+    }
+
+    virtual OwningExprResult ActOnCXXThrow(SourceLocation OpLoc, ExprArg Op) {
+      llvm::cout << __FUNCTION__ << "\n";
+      return ExprEmpty();
+    }
+
+    virtual OwningExprResult ActOnCXXTypeConstructExpr(SourceRange TypeRange,
+                                                     TypeTy *TypeRep,
+                                                     SourceLocation LParenLoc,
+                                                     MultiExprArg Exprs,
+                                                     SourceLocation *CommaLocs,
+                                                     SourceLocation RParenLoc) {
+      llvm::cout << __FUNCTION__ << "\n";
+      return ExprEmpty();
+    }
+
+    virtual OwningExprResult ActOnCXXConditionDeclarationExpr(Scope *S,
+                                                        SourceLocation StartLoc,
+                                                        Declarator &D,
+                                                        SourceLocation EqualLoc,
+                                                        ExprArg AssignExprVal) {
+      llvm::cout << __FUNCTION__ << "\n";
+      return ExprEmpty();
+    }
+
+    virtual OwningExprResult ActOnCXXNew(SourceLocation StartLoc,
+                                         bool UseGlobal,
+                                         SourceLocation PlacementLParen,
+                                         MultiExprArg PlacementArgs,
+                                         SourceLocation PlacementRParen,
+                                         bool ParenTypeId, Declarator &D,
+                                         SourceLocation ConstructorLParen,
+                                         MultiExprArg ConstructorArgs,
+                                         SourceLocation ConstructorRParen) {
+      llvm::cout << __FUNCTION__ << "\n";
+      return ExprEmpty();
+    }
+
+    virtual OwningExprResult ActOnCXXDelete(SourceLocation StartLoc,
+                                            bool UseGlobal, bool ArrayForm,
+                                            ExprArg Operand) {
+      llvm::cout << __FUNCTION__ << "\n";
+      return ExprEmpty();
+    }
+
+    virtual OwningExprResult ActOnUnaryTypeTrait(UnaryTypeTrait OTT,
+                                                 SourceLocation KWLoc,
+                                                 SourceLocation LParen,
+                                                 TypeTy *Ty,
+                                                 SourceLocation RParen) {
+      llvm::cout << __FUNCTION__ << "\n";
+      return ExprEmpty();
+    }
   };
 }
 
diff --git a/include/clang/Parse/Action.h b/include/clang/Parse/Action.h
index 3df0d1dd7d..f33918eae8 100644
--- a/include/clang/Parse/Action.h
+++ b/include/clang/Parse/Action.h
@@ -730,16 +730,17 @@ public:
 
   //===---------------------- GNU Extension Expressions -------------------===//
 
-  virtual ExprResult ActOnAddrLabel(SourceLocation OpLoc, SourceLocation LabLoc,
-                                    IdentifierInfo *LabelII) { // "&&foo"
-    return 0;
+  virtual OwningExprResult ActOnAddrLabel(SourceLocation OpLoc,
+                                          SourceLocation LabLoc,
+                                          IdentifierInfo *LabelII) { // "&&foo"
+    return ExprEmpty();
   }
-  
-  virtual ExprResult ActOnStmtExpr(SourceLocation LPLoc, StmtTy *SubStmt,
-                                   SourceLocation RPLoc) { // "({..})"
-    return 0;
+
+  virtual OwningExprResult ActOnStmtExpr(SourceLocation LPLoc, StmtArg SubStmt,
+                                         SourceLocation RPLoc) { // "({..})"
+    return ExprEmpty();
   }
-  
+
   // __builtin_offsetof(type, identifier(.identifier|[expr])*)
   struct OffsetOfComponent {
     SourceLocation LocStart, LocEnd;
@@ -749,39 +750,41 @@ public:
       ExprTy *E;
     } U;
   };
-  
-  virtual ExprResult ActOnBuiltinOffsetOf(Scope *S, SourceLocation BuiltinLoc,
-                                          SourceLocation TypeLoc, TypeTy *Arg1,
-                                          OffsetOfComponent *CompPtr,
-                                          unsigned NumComponents,
-                                          SourceLocation RParenLoc) {
-    return 0;
+
+  virtual OwningExprResult ActOnBuiltinOffsetOf(Scope *S,
+                                                SourceLocation BuiltinLoc,
+                                                SourceLocation TypeLoc,
+                                                TypeTy *Arg1,
+                                                OffsetOfComponent *CompPtr,
+                                                unsigned NumComponents,
+                                                SourceLocation RParenLoc) {
+    return ExprEmpty();
   }
-  
+
   // __builtin_types_compatible_p(type1, type2)
-  virtual ExprResult ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 
-                                              TypeTy *arg1, TypeTy *arg2,
-                                              SourceLocation RPLoc) {
-    return 0;
+  virtual OwningExprResult ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 
+                                                    TypeTy *arg1, TypeTy *arg2,
+                                                    SourceLocation RPLoc) {
+    return ExprEmpty();
   }
   // __builtin_choose_expr(constExpr, expr1, expr2)
-  virtual ExprResult ActOnChooseExpr(SourceLocation BuiltinLoc, 
-                                     ExprTy *cond, ExprTy *expr1, ExprTy *expr2,
-                                     SourceLocation RPLoc) {
-    return 0;
+  virtual OwningExprResult ActOnChooseExpr(SourceLocation BuiltinLoc, 
+                                           ExprArg cond, ExprArg expr1,
+                                           ExprArg expr2, SourceLocation RPLoc){
+    return ExprEmpty();
   }
 
   // __builtin_va_arg(expr, type)
-  virtual ExprResult ActOnVAArg(SourceLocation BuiltinLoc,
-                                ExprTy *expr, TypeTy *type,
-                                SourceLocation RPLoc) {
-    return 0;
+  virtual OwningExprResult ActOnVAArg(SourceLocation BuiltinLoc,
+                                      ExprArg expr, TypeTy *type,
+                                      SourceLocation RPLoc) {
+    return ExprEmpty();
   }
 
   /// ActOnGNUNullExpr - Parsed the GNU __null expression, the token
   /// for which is at position TokenLoc.
-  virtual ExprResult ActOnGNUNullExpr(SourceLocation TokenLoc) {
-    return 0;
+  virtual OwningExprResult ActOnGNUNullExpr(SourceLocation TokenLoc) {
+    return ExprEmpty();
   }
 
   //===------------------------- "Block" Extension ------------------------===//
@@ -793,15 +796,18 @@ public:
   /// ActOnBlockArguments - This callback allows processing of block arguments.
   /// If there are no arguments, this is still invoked.
   virtual void ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) {}
-  
+
   /// ActOnBlockError - If there is an error parsing a block, this callback
   /// is invoked to pop the information about the block from the action impl.
   virtual void ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) {}
-  
+
   /// ActOnBlockStmtExpr - This is called when the body of a block statement
   /// literal was successfully completed.  ^(int x){...}
-  virtual ExprResult ActOnBlockStmtExpr(SourceLocation CaretLoc, StmtTy *Body,
-                                        Scope *CurScope) { return 0; }
+  virtual OwningExprResult ActOnBlockStmtExpr(SourceLocation CaretLoc,
+                                              StmtArg Body,
+                                              Scope *CurScope) {
+    return ExprEmpty();
+  }
 
   //===------------------------- C++ Declarations -------------------------===//
 
@@ -831,7 +837,7 @@ public:
   /// ActOnParamDefaultArgument - Parse default argument for function parameter
   virtual void ActOnParamDefaultArgument(DeclTy *param,
                                          SourceLocation EqualLoc,
-                                         ExprTy *defarg) {
+                                         ExprArg defarg) {
   }
 
   /// ActOnParamUnparsedDefaultArgument - We've seen a default
@@ -850,12 +856,12 @@ public:
   /// e.g: "int x(1);"
   virtual void AddCXXDirectInitializerToDecl(DeclTy *Dcl,
                                              SourceLocation LParenLoc,
-                                             ExprTy **Exprs, unsigned NumExprs,
+                                             MultiExprArg Exprs,
                                              SourceLocation *CommaLocs,
                                              SourceLocation RParenLoc) {
     return;
   }
-  
+
   /// ActOnStartDelayedCXXMethodDeclaration - We have completed
   /// parsing a top-level (non-nested) C++ class, and we are now
   /// parsing those parts of the given Method declaration that could
@@ -881,76 +887,78 @@ public:
   /// ActOnStartOfFunctionDef action later (not necessarily
   /// immediately!) for this method, if it was also defined inside the
   /// class body.
-  virtual void ActOnFinishDelayedCXXMethodDeclaration(Scope *S, DeclTy *Method) {
+  virtual void ActOnFinishDelayedCXXMethodDeclaration(Scope *S, DeclTy *Method){
   }
 
   /// ActOnStaticAssertDeclaration - Parse a C++0x static_assert declaration.
-  virtual DeclTy *ActOnStaticAssertDeclaration(SourceLocation AssertLoc, 
+  virtual DeclTy *ActOnStaticAssertDeclaration(SourceLocation AssertLoc,
                                                ExprArg AssertExpr,
                                                ExprArg AssertMessageExpr,
                                                SourceLocation RParenLoc) {
     return 0;
   }
-  
-                                          
+
+
   //===------------------------- C++ Expressions --------------------------===//
-  
+
   /// ActOnCXXNamedCast - Parse {dynamic,static,reinterpret,const}_cast's.
-  virtual ExprResult ActOnCXXNamedCast(SourceLocation OpLoc, tok::TokenKind Kind,
-                                       SourceLocation LAngleBracketLoc, TypeTy *Ty,
-                                       SourceLocation RAngleBracketLoc,
-                                       SourceLocation LParenLoc, ExprTy *Op,
-                                       SourceLocation RParenLoc) {
-    return 0;
+  virtual OwningExprResult ActOnCXXNamedCast(SourceLocation OpLoc,
+                                             tok::TokenKind Kind,
+                                             SourceLocation LAngleBracketLoc,
+                                             TypeTy *Ty,
+                                             SourceLocation RAngleBracketLoc,
+                                             SourceLocation LParenLoc,
+                                             ExprArg Op,
+                                             SourceLocation RParenLoc) {
+    return ExprEmpty();
   }
 
   /// ActOnCXXTypeidOfType - Parse typeid( type-id ).
-  virtual ExprResult ActOnCXXTypeid(SourceLocation OpLoc,
-                                    SourceLocation LParenLoc, bool isType,
-                                    void *TyOrExpr, SourceLocation RParenLoc) {
-    return 0;
+  virtual OwningExprResult ActOnCXXTypeid(SourceLocation OpLoc,
+                                          SourceLocation LParenLoc, bool isType,
+                                          void *TyOrExpr,
+                                          SourceLocation RParenLoc) {
+    return ExprEmpty();
   }
 
   /// ActOnCXXThis - Parse the C++ 'this' pointer.
-  virtual ExprResult ActOnCXXThis(SourceLocation ThisLoc) {
-    return 0;
+  virtual OwningExprResult ActOnCXXThis(SourceLocation ThisLoc) {
+    return ExprEmpty();
   }
 
   /// ActOnCXXBoolLiteral - Parse {true,false} literals.
-  virtual ExprResult ActOnCXXBoolLiteral(SourceLocation OpLoc,
+  virtual OwningExprResult ActOnCXXBoolLiteral(SourceLocation OpLoc,
                                          tok::TokenKind Kind) {
-    return 0;
+    return ExprEmpty();
   }
 
   /// ActOnCXXThrow - Parse throw expressions.
-  virtual ExprResult ActOnCXXThrow(SourceLocation OpLoc,
-                                   ExprTy *Op = 0) {
-    return 0;
+  virtual OwningExprResult ActOnCXXThrow(SourceLocation OpLoc, ExprArg Op) {
+    return ExprEmpty();
   }
 
   /// ActOnCXXTypeConstructExpr - Parse construction of a specified type.
   /// Can be interpreted either as function-style casting ("int(x)")
   /// or class type construction ("ClassType(x,y,z)")
   /// or creation of a value-initialized type ("int()").
-  virtual ExprResult ActOnCXXTypeConstructExpr(SourceRange TypeRange,
-                                               TypeTy *TypeRep,
-                                               SourceLocation LParenLoc,
-                                               ExprTy **Exprs,
-                                               unsigned NumExprs,
-                                               SourceLocation *CommaLocs,
-                                               SourceLocation RParenLoc) {
-    return 0;
+  virtual OwningExprResult ActOnCXXTypeConstructExpr(SourceRange TypeRange,
+                                                     TypeTy *TypeRep,
+                                                     SourceLocation LParenLoc,
+                                                     MultiExprArg Exprs,
+                                                     SourceLocation *CommaLocs,
+                                                     SourceLocation RParenLoc) {
+    return ExprEmpty();
   }
 
   /// ActOnCXXConditionDeclarationExpr - Parsed a condition declaration of a
   /// C++ if/switch/while/for statement.
   /// e.g: "if (int x = f()) {...}"
-  virtual ExprResult ActOnCXXConditionDeclarationExpr(Scope *S,
+  virtual OwningExprResult ActOnCXXConditionDeclarationExpr(Scope *S,
                                                       SourceLocation StartLoc,
                                                       Declarator &D,
                                                       SourceLocation EqualLoc,
-                                                      ExprTy *AssignExprVal) {
-    return 0;
+                                                      ExprArg AssignExprVal) {
+    return ExprEmpty();
   }
 
   /// ActOnCXXNew - Parsed a C++ 'new' expression. UseGlobal is true if the
@@ -958,23 +966,24 @@ public:
   /// @code new (p1, p2) type(c1, c2) @endcode
   /// the p1 and p2 expressions will be in PlacementArgs and the c1 and c2
   /// expressions in ConstructorArgs. The type is passed as a declarator.
-  virtual ExprResult ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
-                                 SourceLocation PlacementLParen,
-                                 ExprTy **PlacementArgs, unsigned NumPlaceArgs,
-                                 SourceLocation PlacementRParen,
-                                 bool ParenTypeId, Declarator &D,
-                                 SourceLocation ConstructorLParen,
-                                 ExprTy **ConstructorArgs, unsigned NumConsArgs,
-                                 SourceLocation ConstructorRParen) {
-    return 0;
+  virtual OwningExprResult ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
+                                       SourceLocation PlacementLParen,
+                                       MultiExprArg PlacementArgs,
+                                       SourceLocation PlacementRParen,
+                                       bool ParenTypeId, Declarator &D,
+                                       SourceLocation ConstructorLParen,
+                                       MultiExprArg ConstructorArgs,
+                                       SourceLocation ConstructorRParen) {
+    return ExprEmpty();
   }
 
   /// ActOnCXXDelete - Parsed a C++ 'delete' expression. UseGlobal is true if
   /// the delete was qualified (::delete). ArrayForm is true if the array form
   /// was used (delete[]).
-  virtual ExprResult ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal,
-                                    bool ArrayForm, ExprTy *Operand) {
-    return 0;
+  virtual OwningExprResult ActOnCXXDelete(SourceLocation StartLoc,
+                                          bool UseGlobal, bool ArrayForm,
+                                          ExprArg Operand) {
+    return ExprEmpty();
   }
 
   virtual OwningExprResult ActOnUnaryTypeTrait(UnaryTypeTrait OTT,
diff --git a/lib/Parse/MinimalAction.cpp b/lib/Parse/MinimalAction.cpp
index 41ad36c83e..fbda832836 100644
--- a/lib/Parse/MinimalAction.cpp
+++ b/lib/Parse/MinimalAction.cpp
@@ -19,7 +19,7 @@
 #include "llvm/Support/raw_ostream.h"
 using namespace clang;
 
-///  Out-of-line virtual destructor to provide home for Action class.
+///  Out-of-line virtual destructor to provide home for ActionBase class.
 ActionBase::~ActionBase() {}
 
 ///  Out-of-line virtual destructor to provide home for Action class.
diff --git a/lib/Parse/ParseCXXInlineMethods.cpp b/lib/Parse/ParseCXXInlineMethods.cpp
index cc61f0f6fd..3ed9802026 100644
--- a/lib/Parse/ParseCXXInlineMethods.cpp
+++ b/lib/Parse/ParseCXXInlineMethods.cpp
@@ -98,7 +98,7 @@ void Parser::ParseLexedMethodDeclarations() {
           Actions.ActOnParamDefaultArgumentError(LM.DefaultArgs[I].Param);
         else
           Actions.ActOnParamDefaultArgument(LM.DefaultArgs[I].Param, EqualLoc,
-                                            DefArgResult.release());
+                                            move(DefArgResult));
         delete Toks;
         LM.DefaultArgs[I].Toks = 0;
       }
diff --git a/lib/Parse/ParseDecl.cpp b/lib/Parse/ParseDecl.cpp
index 56a1decb59..aa96db540a 100644
--- a/lib/Parse/ParseDecl.cpp
+++ b/lib/Parse/ParseDecl.cpp
@@ -346,7 +346,7 @@ ParseInitDeclaratorListAfterFirstDeclarator(Declarator &D) {
         assert(!Exprs.empty() && Exprs.size()-1 == CommaLocs.size() &&
                "Unexpected number of commas!");
         Actions.AddCXXDirectInitializerToDecl(LastDeclInGroup, LParenLoc,
-                                              Exprs.take(), Exprs.size(),
+                                              move_arg(Exprs),
                                               &CommaLocs[0], RParenLoc);
       }
     } else {
@@ -2184,7 +2184,7 @@ void Parser::ParseFunctionDeclarator(SourceLocation LParenLoc, Declarator &D,
           } else {
             // Inform the actions module about the default argument
             Actions.ActOnParamDefaultArgument(Param, EqualLoc,
-                                              DefArgResult.release());
+                                              move(DefArgResult));
           }
         }
       }
diff --git a/lib/Parse/ParseExpr.cpp b/lib/Parse/ParseExpr.cpp
index 000cb9d606..f2892c1367 100644
--- a/lib/Parse/ParseExpr.cpp
+++ b/lib/Parse/ParseExpr.cpp
@@ -625,7 +625,7 @@ Parser::OwningExprResult Parser::ParseCastExpression(bool isUnaryExpression,
   case tok::kw___builtin_types_compatible_p:
     return ParseBuiltinPrimaryExpression();
   case tok::kw___null:
-    return Owned(Actions.ActOnGNUNullExpr(ConsumeToken()));
+    return Actions.ActOnGNUNullExpr(ConsumeToken());
     break;
   case tok::plusplus:      // unary-expression: '++' unary-expression
   case tok::minusminus: {  // unary-expression: '--' unary-expression
@@ -995,8 +995,7 @@ Parser::OwningExprResult Parser::ParseBuiltinPrimaryExpression() {
     if (Ty.isInvalid())
       Res = ExprError();
     else
-      Res = Actions.ActOnVAArg(StartLoc, Expr.release(), Ty.get(), 
-                               ConsumeParen());
+      Res = Actions.ActOnVAArg(StartLoc, move(Expr), Ty.get(), ConsumeParen());
     break;
   }
   case tok::kw___builtin_offsetof: {
@@ -1092,8 +1091,8 @@ Parser::OwningExprResult Parser::ParseBuiltinPrimaryExpression() {
       Diag(Tok, diag::err_expected_rparen);
       return ExprError();
     }
-    Res = Actions.ActOnChooseExpr(StartLoc, Cond.release(), Expr1.release(),
-                                  Expr2.release(), ConsumeParen());
+    Res = Actions.ActOnChooseExpr(StartLoc, move(Cond), move(Expr1),
+                                  move(Expr2), ConsumeParen());
     break;
   }
   case tok::kw___builtin_types_compatible_p:
@@ -1151,8 +1150,7 @@ Parser::ParseParenExpression(ParenParseOption &ExprType,
 
     // If the substmt parsed correctly, build the AST node.
     if (!Stmt.isInvalid() && Tok.is(tok::r_paren))
-      Result = Actions.ActOnStmtExpr(
-        OpenLoc, Stmt.release(), Tok.getLocation());
+      Result = Actions.ActOnStmtExpr(OpenLoc, move(Stmt), Tok.getLocation());
 
   } else if (ExprType >= CompoundLiteral && isTypeIdInParens()) {
     // Otherwise, this is a compound literal expression or cast expression.
@@ -1344,7 +1342,7 @@ Parser::OwningExprResult Parser::ParseBlockLiteralExpression() {
   if (Tok.is(tok::l_brace)) {
     OwningStmtResult Stmt(ParseCompoundStatementBody());
     if (!Stmt.isInvalid()) {
-      Result = Actions.ActOnBlockStmtExpr(CaretLoc, Stmt.release(), CurScope);
+      Result = Actions.ActOnBlockStmtExpr(CaretLoc, move(Stmt), CurScope);
     } else {
       Actions.ActOnBlockError(CaretLoc, CurScope);
     }
diff --git a/lib/Parse/ParseExprCXX.cpp b/lib/Parse/ParseExprCXX.cpp
index 50e6657ad8..e1b5db9c44 100644
--- a/lib/Parse/ParseExprCXX.cpp
+++ b/lib/Parse/ParseExprCXX.cpp
@@ -328,9 +328,9 @@ Parser::OwningExprResult Parser::ParseCXXCasts() {
 
   if (!Result.isInvalid() && !CastTy.isInvalid())
     Result = Actions.ActOnCXXNamedCast(OpLoc, Kind,
-                                       LAngleBracketLoc, CastTy.get(), 
+                                       LAngleBracketLoc, CastTy.get(),
                                        RAngleBracketLoc,
-                                       LParenLoc, Result.release(), RParenLoc);
+                                       LParenLoc, move(Result), RParenLoc);
 
   return move(Result);
 }
@@ -390,7 +390,7 @@ Parser::OwningExprResult Parser::ParseCXXTypeid() {
 ///         'false'
 Parser::OwningExprResult Parser::ParseCXXBoolLiteral() {
   tok::TokenKind Kind = Tok.getKind();
-  return Owned(Actions.ActOnCXXBoolLiteral(ConsumeToken(), Kind));
+  return Actions.ActOnCXXBoolLiteral(ConsumeToken(), Kind);
 }
 
 /// ParseThrowExpression - This handles the C++ throw expression.
@@ -411,12 +411,12 @@ Parser::OwningExprResult Parser::ParseThrowExpression() {
   case tok::r_brace:
   case tok::colon:
   case tok::comma:
-    return Owned(Actions.ActOnCXXThrow(ThrowLoc));
+    return Actions.ActOnCXXThrow(ThrowLoc, ExprArg(Actions));
 
   default:
     OwningExprResult Expr(ParseAssignmentExpression());
     if (Expr.isInvalid()) return move(Expr);
-    return Owned(Actions.ActOnCXXThrow(ThrowLoc, Expr.release()));
+    return Actions.ActOnCXXThrow(ThrowLoc, move(Expr));
   }
 }
 
@@ -428,7 +428,7 @@ Parser::OwningExprResult Parser::ParseThrowExpression() {
 Parser::OwningExprResult Parser::ParseCXXThis() {
   assert(Tok.is(tok::kw_this) && "Not 'this'!");
   SourceLocation ThisLoc = ConsumeToken();
-  return Owned(Actions.ActOnCXXThis(ThisLoc));
+  return Actions.ActOnCXXThis(ThisLoc);
 }
 
 /// ParseCXXTypeConstructExpression - Parse construction of a specified type.
@@ -463,10 +463,9 @@ Parser::ParseCXXTypeConstructExpression(const DeclSpec &DS) {
 
   assert((Exprs.size() == 0 || Exprs.size()-1 == CommaLocs.size())&&
          "Unexpected number of commas!");
-  return Owned(Actions.ActOnCXXTypeConstructExpr(DS.getSourceRange(), TypeRep,
-                                                 LParenLoc,
-                                                 Exprs.take(), Exprs.size(),
-                                                 &CommaLocs[0], RParenLoc));
+  return Actions.ActOnCXXTypeConstructExpr(DS.getSourceRange(), TypeRep,
+                                           LParenLoc, move_arg(Exprs),
+                                           &CommaLocs[0], RParenLoc);
 }
 
 /// ParseCXXCondition - if/switch/while/for condition expression.
@@ -518,9 +517,9 @@ Parser::OwningExprResult Parser::ParseCXXCondition() {
   if (AssignExpr.isInvalid())
     return ExprError();
 
-  return Owned(Actions.ActOnCXXConditionDeclarationExpr(CurScope, StartLoc,
-                                                        DeclaratorInfo,EqualLoc,
-                                                        AssignExpr.release()));
+  return Actions.ActOnCXXConditionDeclarationExpr(CurScope, StartLoc,
+                                                  DeclaratorInfo,EqualLoc,
+                                                  move(AssignExpr));
 }
 
 /// ParseCXXSimpleTypeSpecifier - [C++ 7.1.5.2] Simple type specifiers.
@@ -883,11 +882,10 @@ Parser::ParseCXXNewExpression(bool UseGlobal, SourceLocation Start) {
     }
   }
 
-  return Owned(Actions.ActOnCXXNew(Start, UseGlobal, PlacementLParen,
-                                   PlacementArgs.take(), PlacementArgs.size(),
-                                   PlacementRParen, ParenTypeId, DeclaratorInfo,
-                                   ConstructorLParen, ConstructorArgs.take(),
-                                   ConstructorArgs.size(), ConstructorRParen));
+  return Actions.ActOnCXXNew(Start, UseGlobal, PlacementLParen,
+                             move_arg(PlacementArgs), PlacementRParen,
+                             ParenTypeId, DeclaratorInfo, ConstructorLParen,
+                             move_arg(ConstructorArgs), ConstructorRParen);
 }
 
 /// ParseDirectNewDeclarator - Parses a direct-new-declarator. Intended to be
@@ -977,8 +975,7 @@ Parser::ParseCXXDeleteExpression(bool UseGlobal, SourceLocation Start) {
   if (Operand.isInvalid())
     return move(Operand);
 
-  return Owned(Actions.ActOnCXXDelete(Start, UseGlobal, ArrayDelete,
-                                      Operand.release()));
+  return Actions.ActOnCXXDelete(Start, UseGlobal, ArrayDelete, move(Operand));
 }
 
 static UnaryTypeTrait UnaryTypeTraitFromTokKind(tok::TokenKind kind)
diff --git a/lib/Sema/Sema.h b/lib/Sema/Sema.h
index 54b3d197fa..6647945364 100644
--- a/lib/Sema/Sema.h
+++ b/lib/Sema/Sema.h
@@ -326,9 +326,9 @@ public:
                                      bool IsFunctionDefinition,
                                      bool& InvalidDecl, bool &Redeclaration);
   virtual DeclTy *ActOnParamDeclarator(Scope *S, Declarator &D);
-  virtual void ActOnParamDefaultArgument(DeclTy *param, 
+  virtual void ActOnParamDefaultArgument(DeclTy *param,
                                          SourceLocation EqualLoc,
-                                         ExprTy *defarg);
+                                         ExprArg defarg);
   virtual void ActOnParamUnparsedDefaultArgument(DeclTy *param, 
                                                  SourceLocation EqualLoc);
   virtual void ActOnParamDefaultArgumentError(DeclTy *param);
@@ -1266,63 +1266,65 @@ public:
                                               ExprArg RHS);
 
   /// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo".
-  virtual ExprResult ActOnAddrLabel(SourceLocation OpLoc, SourceLocation LabLoc,
-                                    IdentifierInfo *LabelII);
-  
-  virtual ExprResult ActOnStmtExpr(SourceLocation LPLoc, StmtTy *SubStmt,
-                                   SourceLocation RPLoc); // "({..})"
+  virtual OwningExprResult ActOnAddrLabel(SourceLocation OpLoc,
+                                          SourceLocation LabLoc,
+                                          IdentifierInfo *LabelII);
+
+  virtual OwningExprResult ActOnStmtExpr(SourceLocation LPLoc, StmtArg SubStmt,
+                                         SourceLocation RPLoc); // "({..})"
 
   /// __builtin_offsetof(type, a.b[123][456].c)
-  virtual ExprResult ActOnBuiltinOffsetOf(Scope *S,
-                                          SourceLocation BuiltinLoc,
-                                          SourceLocation TypeLoc, TypeTy *Arg1,
-                                          OffsetOfComponent *CompPtr,
-                                          unsigned NumComponents,
-                                          SourceLocation RParenLoc);
-    
+  virtual OwningExprResult ActOnBuiltinOffsetOf(Scope *S,
+                                                SourceLocation BuiltinLoc,
+                                                SourceLocation TypeLoc,
+                                                TypeTy *Arg1,
+                                                OffsetOfComponent *CompPtr,
+                                                unsigned NumComponents,
+                                                SourceLocation RParenLoc);
+
   // __builtin_types_compatible_p(type1, type2)
-  virtual ExprResult ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 
-                                              TypeTy *arg1, TypeTy *arg2,
-                                              SourceLocation RPLoc);
-                                              
+  virtual OwningExprResult ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc,
+                                                    TypeTy *arg1, TypeTy *arg2,
+                                                    SourceLocation RPLoc);
+
   // __builtin_choose_expr(constExpr, expr1, expr2)
-  virtual ExprResult ActOnChooseExpr(SourceLocation BuiltinLoc, 
-                                     ExprTy *cond, ExprTy *expr1, ExprTy *expr2,
-                                     SourceLocation RPLoc);
-  
+  virtual OwningExprResult ActOnChooseExpr(SourceLocation BuiltinLoc,
+                                           ExprArg cond, ExprArg expr1,
+                                           ExprArg expr2, SourceLocation RPLoc);
+
   // __builtin_va_arg(expr, type)
-  virtual ExprResult ActOnVAArg(SourceLocation BuiltinLoc,
-                                ExprTy *expr, TypeTy *type,
-                                SourceLocation RPLoc);
+  virtual OwningExprResult ActOnVAArg(SourceLocation BuiltinLoc,
+                                      ExprArg expr, TypeTy *type,
+                                      SourceLocation RPLoc);
 
   // __null
-  virtual ExprResult ActOnGNUNullExpr(SourceLocation TokenLoc);
+  virtual OwningExprResult ActOnGNUNullExpr(SourceLocation TokenLoc);
 
   //===------------------------- "Block" Extension ------------------------===//
 
   /// ActOnBlockStart - This callback is invoked when a block literal is
   /// started.
   virtual void ActOnBlockStart(SourceLocation CaretLoc, Scope *CurScope);
-  
+
   /// ActOnBlockArguments - This callback allows processing of block arguments.
   /// If there are no arguments, this is still invoked.
   virtual void ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope);
-  
+
   /// ActOnBlockError - If there is an error parsing a block, this callback
   /// is invoked to pop the information about the block from the action impl.
   virtual void ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope);
-  
+
   /// ActOnBlockStmtExpr - This is called when the body of a block statement
   /// literal was successfully completed.  ^(int x){...}
-  virtual ExprResult ActOnBlockStmtExpr(SourceLocation CaretLoc, StmtTy *Body,
-                                        Scope *CurScope);
+  virtual OwningExprResult ActOnBlockStmtExpr(SourceLocation CaretLoc,
+                                              StmtArg Body, Scope *CurScope);
 
   //===---------------------------- C++ Features --------------------------===//
 
   // Act on C++ namespaces
   virtual DeclTy *ActOnStartNamespaceDef(Scope *S, SourceLocation IdentLoc,
-                                        IdentifierInfo *Ident,
-                                        SourceLocation LBrace);
+                                         IdentifierInfo *Ident,
+                                         SourceLocation LBrace);
   virtual void ActOnFinishNamespaceDef(DeclTy *Dcl, SourceLocation RBrace);
 
   virtual DeclTy *ActOnUsingDirective(Scope *CurScope,
@@ -1340,7 +1342,7 @@ public:
   /// e.g: "int x(1);"
   virtual void AddCXXDirectInitializerToDecl(DeclTy *Dcl,
                                              SourceLocation LParenLoc,
-                                             ExprTy **Exprs, unsigned NumExprs,
+                                             MultiExprArg Exprs,
                                              SourceLocation *CommaLocs,
                                              SourceLocation RParenLoc);
 
@@ -1360,49 +1362,52 @@ public:
                                      InitializationKind Kind);
 
   /// ActOnCXXNamedCast - Parse {dynamic,static,reinterpret,const}_cast's.
-  virtual ExprResult ActOnCXXNamedCast(SourceLocation OpLoc, tok::TokenKind Kind,
-                                       SourceLocation LAngleBracketLoc, TypeTy *Ty,
-                                       SourceLocation RAngleBracketLoc,
-                                       SourceLocation LParenLoc, ExprTy *E,
-                                       SourceLocation RParenLoc);
+  virtual OwningExprResult ActOnCXXNamedCast(SourceLocation OpLoc,
+                                             tok::TokenKind Kind,
+                                             SourceLocation LAngleBracketLoc,
+                                             TypeTy *Ty,
+                                             SourceLocation RAngleBracketLoc,
+                                             SourceLocation LParenLoc,
+                                             ExprArg E,
+                                             SourceLocation RParenLoc);
 
-  /// ActOnCXXTypeidOfType - Parse typeid( type-id ).
-  virtual ExprResult ActOnCXXTypeid(SourceLocation OpLoc,
-                                    SourceLocation LParenLoc, bool isType,
-                                    void *TyOrExpr, SourceLocation RParenLoc);
+  /// ActOnCXXTypeid - Parse typeid( something ).
+  virtual OwningExprResult ActOnCXXTypeid(SourceLocation OpLoc,
+                                          SourceLocation LParenLoc, bool isType,
+                                          void *TyOrExpr,
+                                          SourceLocation RParenLoc);
 
   //// ActOnCXXThis -  Parse 'this' pointer.
-  virtual ExprResult ActOnCXXThis(SourceLocation ThisLoc);
+  virtual OwningExprResult ActOnCXXThis(SourceLocation ThisLoc);
 
   /// ActOnCXXBoolLiteral - Parse {true,false} literals.
-  virtual ExprResult ActOnCXXBoolLiteral(SourceLocation OpLoc,
-                                         tok::TokenKind Kind);
-  
+  virtual OwningExprResult ActOnCXXBoolLiteral(SourceLocation OpLoc,
+                                               tok::TokenKind Kind);
+
   //// ActOnCXXThrow -  Parse throw expressions.
-  virtual ExprResult ActOnCXXThrow(SourceLocation OpLoc,
-                                   ExprTy *expr);
+  virtual OwningExprResult ActOnCXXThrow(SourceLocation OpLoc,
+                                         ExprArg expr);
 
   /// ActOnCXXTypeConstructExpr - Parse construction of a specified type.
   /// Can be interpreted either as function-style casting ("int(x)")
   /// or class type construction ("ClassType(x,y,z)")
   /// or creation of a value-initialized type ("int()").
-  virtual ExprResult ActOnCXXTypeConstructExpr(SourceRange TypeRange,
-                                               TypeTy *TypeRep,
-                                               SourceLocation LParenLoc,
-                                               ExprTy **Exprs,
-                                               unsigned NumExprs,
-                                               SourceLocation *CommaLocs,
-                                               SourceLocation RParenLoc);
+  virtual OwningExprResult ActOnCXXTypeConstructExpr(SourceRange TypeRange,
+                                                     TypeTy *TypeRep,
+                                                     SourceLocation LParenLoc,
+                                                     MultiExprArg Exprs,
+                                                     SourceLocation *CommaLocs,
+                                                     SourceLocation RParenLoc);
 
   /// ActOnCXXNew - Parsed a C++ 'new' expression.
-  virtual ExprResult ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
-                                 SourceLocation PlacementLParen,
-                                 ExprTy **PlacementArgs, unsigned NumPlaceArgs,
-                                 SourceLocation PlacementRParen,
-                                 bool ParenTypeId, Declarator &D,
-                                 SourceLocation ConstructorLParen,
-                                 ExprTy **ConstructorArgs, unsigned NumConsArgs,
-                                 SourceLocation ConstructorRParen);
+  virtual OwningExprResult ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
+                                       SourceLocation PlacementLParen,
+                                       MultiExprArg PlacementArgs,
+                                       SourceLocation PlacementRParen,
+                                       bool ParenTypeId, Declarator &D,
+                                       SourceLocation ConstructorLParen,
+                                       MultiExprArg ConstructorArgs,
+                                       SourceLocation ConstructorRParen);
   bool CheckAllocatedType(QualType AllocType, const Declarator &D);
   bool FindAllocationFunctions(SourceLocation StartLoc, SourceRange Range,
                                bool UseGlobal, QualType AllocType, bool IsArray,
@@ -1418,17 +1423,18 @@ public:
                                        QualType Argument);
 
   /// ActOnCXXDelete - Parsed a C++ 'delete' expression
-  virtual ExprResult ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal,
-                                    bool ArrayForm, ExprTy *Operand);
+  virtual OwningExprResult ActOnCXXDelete(SourceLocation StartLoc,
+                                          bool UseGlobal, bool ArrayForm,
+                                          ExprArg Operand);
 
   /// ActOnCXXConditionDeclarationExpr - Parsed a condition declaration of a
   /// C++ if/switch/while/for statement.
   /// e.g: "if (int x = f()) {...}"
-  virtual ExprResult ActOnCXXConditionDeclarationExpr(Scope *S,
+  virtual OwningExprResult ActOnCXXConditionDeclarationExpr(Scope *S,
                                                       SourceLocation StartLoc,
                                                       Declarator &D,
                                                       SourceLocation EqualLoc,
-                                                      ExprTy *AssignExprVal);
+                                                      ExprArg AssignExprVal);
 
   /// ActOnUnaryTypeTrait - Parsed one of the unary type trait support
   /// pseudo-functions.
diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index 0123fe0af2..177eee2a53 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -105,9 +105,9 @@ namespace {
 /// to the parameter declaration.
 void
 Sema::ActOnParamDefaultArgument(DeclTy *param, SourceLocation EqualLoc, 
-                                ExprTy *defarg) {
+                                ExprArg defarg) {
   ParmVarDecl *Param = (ParmVarDecl *)param;
-  ExprOwningPtr<Expr> DefaultArg(this, (Expr *)defarg);
+  ExprOwningPtr<Expr> DefaultArg(this, (Expr *)defarg.release());
   QualType ParamType = Param->getType();
 
   // Default arguments are only permitted in C++
@@ -1448,17 +1448,16 @@ void Sema::PushUsingDirective(Scope *S, UsingDirectiveDecl *UDir) {
 /// ActOnDeclarator, when a C++ direct initializer is present.
 /// e.g: "int x(1);"
 void Sema::AddCXXDirectInitializerToDecl(DeclTy *Dcl, SourceLocation LParenLoc,
-                                         ExprTy **ExprTys, unsigned NumExprs,
+                                         MultiExprArg Exprs,
                                          SourceLocation *CommaLocs,
                                          SourceLocation RParenLoc) {
-  assert(NumExprs != 0 && ExprTys && "missing expressions");
+  unsigned NumExprs = Exprs.size();
+  assert(NumExprs != 0 && Exprs.get() && "missing expressions");
   Decl *RealDecl = static_cast<Decl *>(Dcl);
 
   // If there is no declaration, there was an error parsing it.  Just ignore
   // the initializer.
   if (RealDecl == 0) {
-    for (unsigned i = 0; i != NumExprs; ++i)
-      static_cast<Expr *>(ExprTys[i])->Destroy(Context);
     return;
   }
   
@@ -1489,16 +1488,17 @@ void Sema::AddCXXDirectInitializerToDecl(DeclTy *Dcl, SourceLocation LParenLoc,
 
   if (VDecl->getType()->isRecordType()) {
     CXXConstructorDecl *Constructor
-      = PerformInitializationByConstructor(DeclInitType, 
-                                           (Expr **)ExprTys, NumExprs,
+      = PerformInitializationByConstructor(DeclInitType,
+                                           (Expr **)Exprs.get(), NumExprs,
                                            VDecl->getLocation(),
                                            SourceRange(VDecl->getLocation(),
                                                        RParenLoc),
                                            VDecl->getDeclName(),
                                            IK_Direct);
-    if (!Constructor) {
+    if (!Constructor)
       RealDecl->setInvalidDecl();
-    }
+    else
+      Exprs.release();
 
     // Let clients know that initialization was done with a direct
     // initializer.
@@ -1521,7 +1521,8 @@ void Sema::AddCXXDirectInitializerToDecl(DeclTy *Dcl, SourceLocation LParenLoc,
 
   assert(NumExprs == 1 && "Expected 1 expression");
   // Set the init expression, handles conversions.
-  AddInitializerToDecl(Dcl, ExprArg(*this, ExprTys[0]), /*DirectInit=*/true);
+  AddInitializerToDecl(Dcl, ExprArg(*this, Exprs.release()[0]),
+                       /*DirectInit=*/true);
 }
 
 /// PerformInitializationByConstructor - Perform initialization by
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index c3ae4f7f67..0893bc7fb3 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -4152,9 +4152,9 @@ Action::OwningExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc,
 }
 
 /// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo".
-Sema::ExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc,
-                                      SourceLocation LabLoc,
-                                      IdentifierInfo *LabelII) {
+Sema::OwningExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc,
+                                            SourceLocation LabLoc,
+                                            IdentifierInfo *LabelII) {
   // Look up the record for this label identifier.
   LabelStmt *&LabelDecl = CurBlock ? CurBlock->LabelMap[LabelII] : 
                                      LabelMap[LabelII];
@@ -4165,19 +4165,20 @@ Sema::ExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc,
     LabelDecl = new (Context) LabelStmt(LabLoc, LabelII, 0);
 
   // Create the AST node.  The address of a label always has type 'void*'.
-  return new (Context) AddrLabelExpr(OpLoc, LabLoc, LabelDecl,
-                                     Context.getPointerType(Context.VoidTy));
+  return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, LabelDecl,
+                                       Context.getPointerType(Context.VoidTy)));
 }
 
-Sema::ExprResult Sema::ActOnStmtExpr(SourceLocation LPLoc, StmtTy *substmt,
-                                     SourceLocation RPLoc) { // "({..})"
-  Stmt *SubStmt = static_cast<Stmt*>(substmt);
+Sema::OwningExprResult
+Sema::ActOnStmtExpr(SourceLocation LPLoc, StmtArg substmt,
+                    SourceLocation RPLoc) { // "({..})"
+  Stmt *SubStmt = static_cast<Stmt*>(substmt.get());
   assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!");
   CompoundStmt *Compound = cast<CompoundStmt>(SubStmt);
 
   bool isFileScope = getCurFunctionOrMethodDecl() == 0;
   if (isFileScope) {
-    return Diag(LPLoc, diag::err_stmtexpr_file_scope);
+    return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope));
   }
 
   // FIXME: there are a variety of strange constraints to enforce here, for
@@ -4201,16 +4202,19 @@ Sema::ExprResult Sema::ActOnStmtExpr(SourceLocation LPLoc, StmtTy *substmt,
       Ty = LastExpr->getType();
   }
 
-  return new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc);
+  substmt.release();
+  return Owned(new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc));
 }
 
-Sema::ExprResult Sema::ActOnBuiltinOffsetOf(Scope *S,
-                                            SourceLocation BuiltinLoc,
-                                            SourceLocation TypeLoc,
-                                            TypeTy *argty,
-                                            OffsetOfComponent *CompPtr,
-                                            unsigned NumComponents,
-                                            SourceLocation RPLoc) {
+Sema::OwningExprResult Sema::ActOnBuiltinOffsetOf(Scope *S,
+                                                  SourceLocation BuiltinLoc,
+                                                  SourceLocation TypeLoc,
+                                                  TypeTy *argty,
+                                                  OffsetOfComponent *CompPtr,
+                                                  unsigned NumComponents,
+                                                  SourceLocation RPLoc) {
+  // FIXME: This function leaks all expressions in the offset components on
+  // error.
   QualType ArgTy = QualType::getFromOpaquePtr(argty);
   assert(!ArgTy.isNull() && "Missing type argument!");
 
@@ -4220,7 +4224,7 @@ Sema::ExprResult Sema::ActOnBuiltinOffsetOf(Scope *S,
   // one is known to be a field designator.  Verify that the ArgTy represents
   // a struct/union/class.
   if (!Dependent && !ArgTy->isRecordType())
-    return Diag(TypeLoc, diag::err_offsetof_record_type) << ArgTy;
+    return ExprError(Diag(TypeLoc, diag::err_offsetof_record_type) << ArgTy);
 
   // FIXME: Does the type need to be complete?
 
@@ -4228,7 +4232,7 @@ Sema::ExprResult Sema::ActOnBuiltinOffsetOf(Scope *S,
   // the offsetof designators.
   QualType ArgTyPtr = Context.getPointerType(ArgTy);
   Expr* Res = new (Context) ImplicitValueInitExpr(ArgTyPtr);
-  Res = new (Context) UnaryOperator(Res, UnaryOperator::Deref, 
+  Res = new (Context) UnaryOperator(Res, UnaryOperator::Deref,
                                     ArgTy, SourceLocation());
 
   // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a
@@ -4249,8 +4253,8 @@ Sema::ExprResult Sema::ActOnBuiltinOffsetOf(Scope *S,
         const ArrayType *AT = Context.getAsArrayType(Res->getType());
         if (!AT) {
           Res->Destroy(Context);
-          return Diag(OC.LocEnd, diag::err_offsetof_array_type)
-            << Res->getType();
+          return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type)
+            << Res->getType());
         }
 
         // FIXME: C++: Verify that operator[] isn't overloaded.
@@ -4261,9 +4265,11 @@ Sema::ExprResult Sema::ActOnBuiltinOffsetOf(Scope *S,
 
         // C99 6.5.2.1p1
         Expr *Idx = static_cast<Expr*>(OC.U.E);
+        // FIXME: Leaks Res
         if (!Idx->isTypeDependent() && !Idx->getType()->isIntegerType())
-          return Diag(Idx->getLocStart(), diag::err_typecheck_subscript)
-            << Idx->getSourceRange();
+          return ExprError(Diag(Idx->getLocStart(),
+                                diag::err_typecheck_subscript)
+            << Idx->getSourceRange());
 
         Res = new (Context) ArraySubscriptExpr(Res, Idx, AT->getElementType(),
                                                OC.LocEnd);
@@ -4273,8 +4279,8 @@ Sema::ExprResult Sema::ActOnBuiltinOffsetOf(Scope *S,
       const RecordType *RC = Res->getType()->getAsRecordType();
       if (!RC) {
         Res->Destroy(Context);
-        return Diag(OC.LocEnd, diag::err_offsetof_record_type)
-          << Res->getType();
+        return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type)
+          << Res->getType());
       }
 
       // Get the decl corresponding to this.
@@ -4283,9 +4289,10 @@ Sema::ExprResult Sema::ActOnBuiltinOffsetOf(Scope *S,
         = dyn_cast_or_null<FieldDecl>(LookupQualifiedName(RD, OC.U.IdentInfo,
                                                           LookupMemberName)
                                         .getAsDecl());
+      // FIXME: Leaks Res
       if (!MemberDecl)
-        return Diag(BuiltinLoc, diag::err_typecheck_no_member)
-         << OC.U.IdentInfo << SourceRange(OC.LocStart, OC.LocEnd);
+        return ExprError(Diag(BuiltinLoc, diag::err_typecheck_no_member)
+         << OC.U.IdentInfo << SourceRange(OC.LocStart, OC.LocEnd));
 
       // FIXME: C++: Verify that MemberDecl isn't a static field.
       // FIXME: Verify that MemberDecl isn't a bitfield.
@@ -4296,29 +4303,30 @@ Sema::ExprResult Sema::ActOnBuiltinOffsetOf(Scope *S,
     }
   }
 
-  return new (Context) UnaryOperator(Res, UnaryOperator::OffsetOf,
-                                     Context.getSizeType(), BuiltinLoc);
+  return Owned(new (Context) UnaryOperator(Res, UnaryOperator::OffsetOf,
+                                           Context.getSizeType(), BuiltinLoc));
 }
 
 
-Sema::ExprResult Sema::ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc,
-                                                TypeTy *arg1, TypeTy *arg2,
-                                                SourceLocation RPLoc) {
+Sema::OwningExprResult Sema::ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc,
+                                                      TypeTy *arg1,TypeTy *arg2,
+                                                      SourceLocation RPLoc) {
   QualType argT1 = QualType::getFromOpaquePtr(arg1);
   QualType argT2 = QualType::getFromOpaquePtr(arg2);
 
   assert((!argT1.isNull() && !argT2.isNull()) && "Missing type argument(s)");
 
-  return new (Context) TypesCompatibleExpr(Context.IntTy, BuiltinLoc, argT1,
-                                           argT2, RPLoc);
+  return Owned(new (Context) TypesCompatibleExpr(Context.IntTy, BuiltinLoc,
+                                                 argT1, argT2, RPLoc));
 }
 
-Sema::ExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, ExprTy *cond,
-                                       ExprTy *expr1, ExprTy *expr2,
-                                       SourceLocation RPLoc) {
-  Expr *CondExpr = static_cast<Expr*>(cond);
-  Expr *LHSExpr = static_cast<Expr*>(expr1);
-  Expr *RHSExpr = static_cast<Expr*>(expr2);
+Sema::OwningExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc,
+                                             ExprArg cond,
+                                             ExprArg expr1, ExprArg expr2,
+                                             SourceLocation RPLoc) {
+  Expr *CondExpr = static_cast<Expr*>(cond.get());
+  Expr *LHSExpr = static_cast<Expr*>(expr1.get());
+  Expr *RHSExpr = static_cast<Expr*>(expr2.get());
 
   assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)");
 
@@ -4330,15 +4338,17 @@ Sema::ExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, ExprTy *cond,
     llvm::APSInt condEval(32);
     SourceLocation ExpLoc;
     if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc))
-      return Diag(ExpLoc, diag::err_typecheck_choose_expr_requires_constant)
-        << CondExpr->getSourceRange();
+      return ExprError(Diag(ExpLoc,
+                       diag::err_typecheck_choose_expr_requires_constant)
+        << CondExpr->getSourceRange());
 
     // If the condition is > zero, then the AST type is the same as the LSHExpr.
     resType = condEval.getZExtValue() ? LHSExpr->getType() : RHSExpr->getType();
   }
 
-  return new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr,
-                                  resType, RPLoc);
+  cond.release(); expr1.release(); expr2.release();
+  return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr,
+                                        resType, RPLoc));
 }
 
 //===----------------------------------------------------------------------===//
@@ -4440,11 +4450,10 @@ void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) {
 
 /// ActOnBlockStmtExpr - This is called when the body of a block statement
 /// literal was successfully completed.  ^(int x){...}
-Sema::ExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, StmtTy *body,
-                                          Scope *CurScope) {
+Sema::OwningExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc,
+                                                StmtArg body, Scope *CurScope) {
   // Ensure that CurBlock is deleted.
   llvm::OwningPtr<BlockSemaInfo> BSI(CurBlock);
-  ExprOwningPtr<CompoundStmt> Body(this, static_cast<CompoundStmt*>(body));
 
   PopDeclContext();
 
@@ -4468,14 +4477,14 @@ Sema::ExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, StmtTy *body,
 
   BlockTy = Context.getBlockPointerType(BlockTy);
 
-  BSI->TheDecl->setBody(Body.take());
-  return new (Context) BlockExpr(BSI->TheDecl, BlockTy, BSI->hasBlockDeclRefExprs);
+  BSI->TheDecl->setBody(static_cast<CompoundStmt*>(body.release()));
+  return Owned(new (Context) BlockExpr(BSI->TheDecl, BlockTy,
+                                       BSI->hasBlockDeclRefExprs));
 }
 
-Sema::ExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc,
-                                  ExprTy *expr, TypeTy *type,
-                                  SourceLocation RPLoc) {
-  Expr *E = static_cast<Expr*>(expr);
+Sema::OwningExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc,
+                                        ExprArg expr, TypeTy *type,
+                                        SourceLocation RPLoc) {
   QualType T = QualType::getFromOpaquePtr(type);
 
   InitBuiltinVaListType();
@@ -4488,19 +4497,22 @@ Sema::ExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc,
   if (VaListType->isArrayType())
     VaListType = Context.getArrayDecayedType(VaListType);
   // Make sure the input expression also decays appropriately.
+  Expr *E = static_cast<Expr*>(expr.get());
   UsualUnaryConversions(E);
 
   if (CheckAssignmentConstraints(VaListType, E->getType()) != Compatible)
-    return Diag(E->getLocStart(),
-                diag::err_first_argument_to_va_arg_not_of_type_va_list)
-      << E->getType() << E->getSourceRange();
+    return ExprError(Diag(E->getLocStart(),
+                         diag::err_first_argument_to_va_arg_not_of_type_va_list)
+      << E->getType() << E->getSourceRange());
 
   // FIXME: Warn if a non-POD type is passed in.
 
-  return new (Context) VAArgExpr(BuiltinLoc, E, T.getNonReferenceType(), RPLoc);
+  expr.release();
+  return Owned(new (Context) VAArgExpr(BuiltinLoc, E, T.getNonReferenceType(),
+                                       RPLoc));
 }
 
-Sema::ExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) {
+Sema::OwningExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) {
   // The type of __null will be int or long, depending on the size of
   // pointers on the target.
   QualType Ty;
@@ -4509,7 +4521,7 @@ Sema::ExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) {
   else
     Ty = Context.LongTy;
 
-  return new (Context) GNUNullExpr(Ty, TokenLoc);
+  return Owned(new (Context) GNUNullExpr(Ty, TokenLoc));
 }
 
 bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy,
diff --git a/lib/Sema/SemaExprCXX.cpp b/lib/Sema/SemaExprCXX.cpp
index e5a252043e..5450d1949f 100644
--- a/lib/Sema/SemaExprCXX.cpp
+++ b/lib/Sema/SemaExprCXX.cpp
@@ -56,76 +56,81 @@ Sema::ActOnCXXOperatorFunctionIdExpr(Scope *S, SourceLocation OperatorLoc,
 }
 
 /// ActOnCXXTypeidOfType - Parse typeid( type-id ).
-Action::ExprResult
+Action::OwningExprResult
 Sema::ActOnCXXTypeid(SourceLocation OpLoc, SourceLocation LParenLoc,
                      bool isType, void *TyOrExpr, SourceLocation RParenLoc) {
   NamespaceDecl *StdNs = GetStdNamespace();
   if (!StdNs)
-    return Diag(OpLoc, diag::err_need_header_before_typeid);
+    return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid));
   
   IdentifierInfo *TypeInfoII = &PP.getIdentifierTable().get("type_info");
   Decl *TypeInfoDecl = LookupQualifiedName(StdNs, TypeInfoII, LookupTagName);
   RecordDecl *TypeInfoRecordDecl = dyn_cast_or_null<RecordDecl>(TypeInfoDecl);
   if (!TypeInfoRecordDecl)
-    return Diag(OpLoc, diag::err_need_header_before_typeid);
+    return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid));
 
   QualType TypeInfoType = Context.getTypeDeclType(TypeInfoRecordDecl);
 
-  return new (Context) CXXTypeidExpr(isType, TyOrExpr, TypeInfoType.withConst(),
-                                     SourceRange(OpLoc, RParenLoc));
+  return Owned(new (Context) CXXTypeidExpr(isType, TyOrExpr,
+                                           TypeInfoType.withConst(),
+                                           SourceRange(OpLoc, RParenLoc)));
 }
 
 /// ActOnCXXBoolLiteral - Parse {true,false} literals.
-Action::ExprResult
+Action::OwningExprResult
 Sema::ActOnCXXBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind) {
   assert((Kind == tok::kw_true || Kind == tok::kw_false) &&
          "Unknown C++ Boolean value!");
-  return new (Context) CXXBoolLiteralExpr(Kind == tok::kw_true, Context.BoolTy, OpLoc);
+  return Owned(new (Context) CXXBoolLiteralExpr(Kind == tok::kw_true,
+                                                Context.BoolTy, OpLoc));
 }
 
 /// ActOnCXXThrow - Parse throw expressions.
-Action::ExprResult
-Sema::ActOnCXXThrow(SourceLocation OpLoc, ExprTy *E) {
-  return new (Context) CXXThrowExpr((Expr*)E, Context.VoidTy, OpLoc);
+Action::OwningExprResult
+Sema::ActOnCXXThrow(SourceLocation OpLoc, ExprArg E) {
+  return Owned(new (Context) CXXThrowExpr((Expr*)E.release(), Context.VoidTy,
+                                          OpLoc));
 }
 
-Action::ExprResult Sema::ActOnCXXThis(SourceLocation ThisLoc) {
+Action::OwningExprResult Sema::ActOnCXXThis(SourceLocation ThisLoc) {
   /// C++ 9.3.2: In the body of a non-static member function, the keyword this
   /// is a non-lvalue expression whose value is the address of the object for
   /// which the function is called.
 
-  if (!isa<FunctionDecl>(CurContext)) {
-    Diag(ThisLoc, diag::err_invalid_this_use);
-    return ExprResult(true);
-  }
+  if (!isa<FunctionDecl>(CurContext))
+    return ExprError(Diag(ThisLoc, diag::err_invalid_this_use));
 
   if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext))
     if (MD->isInstance())
-      return new (Context) CXXThisExpr(ThisLoc, MD->getThisType(Context));
+      return Owned(new (Context) CXXThisExpr(ThisLoc,
+                                             MD->getThisType(Context)));
 
-  return Diag(ThisLoc, diag::err_invalid_this_use);
+  return ExprError(Diag(ThisLoc, diag::err_invalid_this_use));
 }
 
 /// ActOnCXXTypeConstructExpr - Parse construction of a specified type.
 /// Can be interpreted either as function-style casting ("int(x)")
 /// or class type construction ("ClassType(x,y,z)")
 /// or creation of a value-initialized type ("int()").
-Action::ExprResult
+Action::OwningExprResult
 Sema::ActOnCXXTypeConstructExpr(SourceRange TypeRange, TypeTy *TypeRep,
                                 SourceLocation LParenLoc,
-                                ExprTy **ExprTys, unsigned NumExprs,
+                                MultiExprArg exprs,
                                 SourceLocation *CommaLocs,
                                 SourceLocation RParenLoc) {
   assert(TypeRep && "Missing type!");
   QualType Ty = QualType::getFromOpaquePtr(TypeRep);
-  Expr **Exprs = (Expr**)ExprTys;
+  unsigned NumExprs = exprs.size();
+  Expr **Exprs = (Expr**)exprs.get();
   SourceLocation TyBeginLoc = TypeRange.getBegin();
   SourceRange FullRange = SourceRange(TyBeginLoc, RParenLoc);
 
-  if (Ty->isDependentType() || 
+  if (Ty->isDependentType() ||
       CallExpr::hasAnyTypeDependentArguments(Exprs, NumExprs)) {
-    return new (Context) CXXTemporaryObjectExpr(0, Ty, TyBeginLoc,
-                                                Exprs, NumExprs, RParenLoc);
+    exprs.release();
+    return Owned(new (Context) CXXTemporaryObjectExpr(0, Ty, TyBeginLoc,
+                                                      Exprs, NumExprs,
+                                                      RParenLoc));
   }
 
 
@@ -136,14 +141,16 @@ Sema::ActOnCXXTypeConstructExpr(SourceRange TypeRange, TypeTy *TypeRep,
   //
   if (NumExprs == 1) {
     if (CheckCastTypes(TypeRange, Ty, Exprs[0]))
-      return true;
-    return new (Context) CXXFunctionalCastExpr(Ty.getNonReferenceType(), Ty,
-                                               TyBeginLoc, Exprs[0], RParenLoc);
+      return ExprError();
+    exprs.release();
+    return Owned(new (Context) CXXFunctionalCastExpr(Ty.getNonReferenceType(),
+                                                     Ty, TyBeginLoc, Exprs[0],
+                                                     RParenLoc));
   }
 
   if (const RecordType *RT = Ty->getAsRecordType()) {
     CXXRecordDecl *Record = cast<CXXRecordDecl>(RT->getDecl());
-    
+
     if (NumExprs > 1 || Record->hasUserDeclaredConstructor()) {
       CXXConstructorDecl *Constructor
         = PerformInitializationByConstructor(Ty, Exprs, NumExprs,
@@ -152,12 +159,14 @@ Sema::ActOnCXXTypeConstructExpr(SourceRange TypeRange, TypeTy *TypeRep,
                                                          RParenLoc),
                                              DeclarationName(),
                                              IK_Direct);
-      
+
       if (!Constructor)
-        return true;
+        return ExprError();
 
-      return new (Context) CXXTemporaryObjectExpr(Constructor, Ty, TyBeginLoc, 
-                                        Exprs, NumExprs, RParenLoc);
+      exprs.release();
+      return Owned(new (Context) CXXTemporaryObjectExpr(Constructor, Ty,
+                                                        TyBeginLoc,  Exprs,
+                                                        NumExprs, RParenLoc));
     }
 
     // Fall through to value-initialize an object of class type that
@@ -169,8 +178,9 @@ Sema::ActOnCXXTypeConstructExpr(SourceRange TypeRange, TypeTy *TypeRep,
   // be a class with a suitably declared constructor.
   //
   if (NumExprs > 1)
-    return Diag(CommaLocs[0], diag::err_builtin_func_cast_more_than_one_arg)
-      << FullRange;
+    return ExprError(Diag(CommaLocs[0],
+                          diag::err_builtin_func_cast_more_than_one_arg)
+      << FullRange);
 
   assert(NumExprs == 0 && "Expected 0 expressions");
 
@@ -180,13 +190,15 @@ Sema::ActOnCXXTypeConstructExpr(SourceRange TypeRange, TypeTy *TypeRep,
   // rvalue of the specified type, which is value-initialized.
   //
   if (Ty->isArrayType())
-    return Diag(TyBeginLoc, diag::err_value_init_for_array_type) << FullRange;
+    return ExprError(Diag(TyBeginLoc,
+                          diag::err_value_init_for_array_type) << FullRange);
   if (!Ty->isDependentType() && !Ty->isVoidType() &&
-      RequireCompleteType(TyBeginLoc, Ty, 
-                             diag::err_invalid_incomplete_type_use, FullRange))
-    return true;
+      RequireCompleteType(TyBeginLoc, Ty,
+                          diag::err_invalid_incomplete_type_use, FullRange))
+    return ExprError();
 
-  return new (Context) CXXZeroInitValueExpr(Ty, TyBeginLoc, RParenLoc);
+  exprs.release();
+  return Owned(new (Context) CXXZeroInitValueExpr(Ty, TyBeginLoc, RParenLoc));
 }
 
 
@@ -195,13 +207,12 @@ Sema::ActOnCXXTypeConstructExpr(SourceRange TypeRange, TypeTy *TypeRep,
 /// or
 /// @code ::new Foo(23, "hello") @endcode
 /// For the interpretation of this heap of arguments, consult the base version.
-Action::ExprResult
+Action::OwningExprResult
 Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
-                  SourceLocation PlacementLParen,
-                  ExprTy **PlacementArgs, unsigned NumPlaceArgs,
+                  SourceLocation PlacementLParen, MultiExprArg PlacementArgs,
                   SourceLocation PlacementRParen, bool ParenTypeId,
                   Declarator &D, SourceLocation ConstructorLParen,
-                  ExprTy **ConstructorArgs, unsigned NumConsArgs,
+                  MultiExprArg ConstructorArgs,
                   SourceLocation ConstructorRParen)
 {
   Expr *ArraySize = 0;
@@ -211,21 +222,21 @@ Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
       D.getTypeObject(0).Kind == DeclaratorChunk::Array) {
     DeclaratorChunk &Chunk = D.getTypeObject(0);
     if (Chunk.Arr.hasStatic)
-      return Diag(Chunk.Loc, diag::err_static_illegal_in_new)
-        << D.getSourceRange();
+      return ExprError(Diag(Chunk.Loc, diag::err_static_illegal_in_new)
+        << D.getSourceRange());
     if (!Chunk.Arr.NumElts)
-      return Diag(Chunk.Loc, diag::err_array_new_needs_size)
-        << D.getSourceRange();
+      return ExprError(Diag(Chunk.Loc, diag::err_array_new_needs_size)
+        << D.getSourceRange());
     ArraySize = static_cast<Expr*>(Chunk.Arr.NumElts);
     Skip = 1;
   }
 
   QualType AllocType = GetTypeForDeclarator(D, /*Scope=*/0, Skip);
   if (D.getInvalidType())
-    return true;
+    return ExprError();
 
   if (CheckAllocatedType(AllocType, D))
-    return true;
+    return ExprError();
 
   QualType ResultType = AllocType->isDependentType()
                           ? Context.DependentTy
@@ -239,9 +250,9 @@ Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
   if (ArraySize && !ArraySize->isTypeDependent()) {
     QualType SizeType = ArraySize->getType();
     if (!SizeType->isIntegralType() && !SizeType->isEnumeralType())
-      return Diag(ArraySize->getSourceRange().getBegin(),
-                  diag::err_array_size_not_integral)
-        << SizeType << ArraySize->getSourceRange();
+      return ExprError(Diag(ArraySize->getSourceRange().getBegin(),
+                            diag::err_array_size_not_integral)
+        << SizeType << ArraySize->getSourceRange());
     // Let's see if this is a constant < 0. If so, we reject it out of hand.
     // We don't care about special rules, so we tell the machinery it's not
     // evaluated - it gives us a result in more cases.
@@ -250,23 +261,24 @@ Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
       if (ArraySize->isIntegerConstantExpr(Value, Context, 0, false)) {
         if (Value < llvm::APSInt(
                         llvm::APInt::getNullValue(Value.getBitWidth()), false))
-          return Diag(ArraySize->getSourceRange().getBegin(),
-                      diag::err_typecheck_negative_array_size)
-            << ArraySize->getSourceRange();
+          return ExprError(Diag(ArraySize->getSourceRange().getBegin(),
+                           diag::err_typecheck_negative_array_size)
+            << ArraySize->getSourceRange());
       }
     }
   }
 
   FunctionDecl *OperatorNew = 0;
   FunctionDecl *OperatorDelete = 0;
-  Expr **PlaceArgs = (Expr**)PlacementArgs;
+  Expr **PlaceArgs = (Expr**)PlacementArgs.get();
+  unsigned NumPlaceArgs = PlacementArgs.size();
   if (!AllocType->isDependentType() &&
       !Expr::hasAnyTypeDependentArguments(PlaceArgs, NumPlaceArgs) &&
       FindAllocationFunctions(StartLoc,
                               SourceRange(PlacementLParen, PlacementRParen),
                               UseGlobal, AllocType, ArraySize, PlaceArgs,
                               NumPlaceArgs, OperatorNew, OperatorDelete))
-    return true;
+    return ExprError();
 
   bool Init = ConstructorLParen.isValid();
   // --- Choosing a constructor ---
@@ -287,7 +299,8 @@ Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
   //    to C++0x rules.
   // 2) Otherwise, the object is direct-initialized.
   CXXConstructorDecl *Constructor = 0;
-  Expr **ConsArgs = (Expr**)ConstructorArgs;
+  Expr **ConsArgs = (Expr**)ConstructorArgs.get();
+  unsigned NumConsArgs = ConstructorArgs.size();
   if (AllocType->isDependentType()) {
     // Skip all the checks.
   }
@@ -303,15 +316,13 @@ Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
                       RT->getDecl()->getDeclName(),
                       NumConsArgs != 0 ? IK_Direct : IK_Default);
     if (!Constructor)
-      return true;
+      return ExprError();
   } else {
     if (!Init) {
       // FIXME: Check that no subpart is const.
-      if (AllocType.isConstQualified()) {
-        Diag(StartLoc, diag::err_new_uninitialized_const)
-          << D.getSourceRange();
-        return true;
-      }
+      if (AllocType.isConstQualified())
+        return ExprError(Diag(StartLoc, diag::err_new_uninitialized_const)
+          << D.getSourceRange());
     } else if (NumConsArgs == 0) {
       // Object is value-initialized. Do nothing.
     } else if (NumConsArgs == 1) {
@@ -320,19 +331,22 @@ Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
       if (CheckInitializerTypes(ConsArgs[0], AllocType, StartLoc,
                                 DeclarationName() /*AllocType.getAsString()*/,
                                 /*DirectInit=*/true))
-        return true;
+        return ExprError();
     } else {
-      Diag(StartLoc, diag::err_builtin_direct_init_more_than_one_arg)
-        << SourceRange(ConstructorLParen, ConstructorRParen);
+      return ExprError(Diag(StartLoc,
+                            diag::err_builtin_direct_init_more_than_one_arg)
+        << SourceRange(ConstructorLParen, ConstructorRParen));
     }
   }
 
   // FIXME: Also check that the destructor is accessible. (C++ 5.3.4p16)
 
-  return new (Context) CXXNewExpr(UseGlobal, OperatorNew, PlaceArgs,
+  PlacementArgs.release();
+  ConstructorArgs.release();
+  return Owned(new (Context) CXXNewExpr(UseGlobal, OperatorNew, PlaceArgs,
                         NumPlaceArgs, ParenTypeId, ArraySize, Constructor, Init,
                         ConsArgs, NumConsArgs, OperatorDelete, ResultType,
-                        StartLoc, Init ? ConstructorRParen : SourceLocation());
+                        StartLoc, Init ? ConstructorRParen : SourceLocation()));
 }
 
 /// CheckAllocatedType - Checks that a type is suitable as the allocated type
@@ -576,16 +590,16 @@ void Sema::DeclareGlobalAllocationFunction(DeclarationName Name,
 /// @code ::delete ptr; @endcode
 /// or
 /// @code delete [] ptr; @endcode
-Action::ExprResult
+Action::OwningExprResult
 Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal,
-                     bool ArrayForm, ExprTy *Operand)
+                     bool ArrayForm, ExprArg Operand)
 {
   // C++ 5.3.5p1: "The operand shall have a pointer type, or a class type
   //   having a single conversion function to a pointer type. The result has
   //   type void."
   // DR599 amends "pointer type" to "pointer to object type" in both cases.
 
-  Expr *Ex = (Expr *)Operand;
+  Expr *Ex = (Expr *)Operand.get();
   if (!Ex->isTypeDependent()) {
     QualType Type = Ex->getType();
 
@@ -593,41 +607,39 @@ Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal,
       // FIXME: Find that one conversion function and amend the type.
     }
 
-    if (!Type->isPointerType()) {
-      Diag(StartLoc, diag::err_delete_operand) << Type << Ex->getSourceRange();
-      return true;
-    }
+    if (!Type->isPointerType())
+      return ExprError(Diag(StartLoc, diag::err_delete_operand)
+        << Type << Ex->getSourceRange());
 
     QualType Pointee = Type->getAsPointerType()->getPointeeType();
-    if (!Pointee->isVoidType() && 
+    if (!Pointee->isVoidType() &&
         RequireCompleteType(StartLoc, Pointee, diag::warn_delete_incomplete,
                                Ex->getSourceRange()))
-      return true;
-    else if (!Pointee->isObjectType()) {
-      Diag(StartLoc, diag::err_delete_operand)
-        << Type << Ex->getSourceRange();
-      return true;
-    }
+      return ExprError();
+    else if (!Pointee->isObjectType())
+      return ExprError(Diag(StartLoc, diag::err_delete_operand)
+        << Type << Ex->getSourceRange());
 
     // FIXME: Look up the correct operator delete overload and pass a pointer
     // along.
     // FIXME: Check access and ambiguity of operator delete and destructor.
   }
 
-  return new (Context) CXXDeleteExpr(Context.VoidTy, UseGlobal, ArrayForm, 0,
-                                     Ex, StartLoc);
+  Operand.release();
+  return Owned(new (Context) CXXDeleteExpr(Context.VoidTy, UseGlobal, ArrayForm,
+                                           0, Ex, StartLoc));
 }
 
 
 /// ActOnCXXConditionDeclarationExpr - Parsed a condition declaration of a
 /// C++ if/switch/while/for statement.
 /// e.g: "if (int x = f()) {...}"
-Action::ExprResult
+Action::OwningExprResult
 Sema::ActOnCXXConditionDeclarationExpr(Scope *S, SourceLocation StartLoc,
                                        Declarator &D,
                                        SourceLocation EqualLoc,
-                                       ExprTy *AssignExprVal) {
-  assert(AssignExprVal && "Null assignment expression");
+                                       ExprArg AssignExprVal) {
+  assert(AssignExprVal.get() && "Null assignment expression");
 
   // C++ 6.4p2:
   // The declarator shall not specify a function or an array.
@@ -642,8 +654,8 @@ Sema::ActOnCXXConditionDeclarationExpr(Scope *S, SourceLocation StartLoc,
   if (Ty->isFunctionType()) { // The declarator shall not specify a function...
     // We exit without creating a CXXConditionDeclExpr because a FunctionDecl
     // would be created and CXXConditionDeclExpr wants a VarDecl.
-    return Diag(StartLoc, diag::err_invalid_use_of_function_type)
-      << SourceRange(StartLoc, EqualLoc);
+    return ExprError(Diag(StartLoc, diag::err_invalid_use_of_function_type)
+      << SourceRange(StartLoc, EqualLoc));
   } else if (Ty->isArrayType()) { // ...or an array.
     Diag(StartLoc, diag::err_invalid_use_of_array_type)
       << SourceRange(StartLoc, EqualLoc);
@@ -661,15 +673,15 @@ Sema::ActOnCXXConditionDeclarationExpr(Scope *S, SourceLocation StartLoc,
 
   DeclTy *Dcl = ActOnDeclarator(S, D, 0);
   if (!Dcl)
-    return true;
-  AddInitializerToDecl(Dcl, ExprArg(*this, AssignExprVal));
+    return ExprError();
+  AddInitializerToDecl(Dcl, move(AssignExprVal));
 
   // Mark this variable as one that is declared within a conditional.
   if (VarDecl *VD = dyn_cast<VarDecl>((Decl *)Dcl))
     VD->setDeclaredInCondition(true);
 
-  return new (Context) CXXConditionDeclExpr(StartLoc, EqualLoc,
-                                       cast<VarDecl>(static_cast<Decl *>(Dcl)));
+  return Owned(new (Context) CXXConditionDeclExpr(StartLoc, EqualLoc,
+                                      cast<VarDecl>(static_cast<Decl *>(Dcl))));
 }
 
 /// CheckCXXBooleanCondition - Returns true if a conversion to bool is invalid.
diff --git a/lib/Sema/SemaNamedCast.cpp b/lib/Sema/SemaNamedCast.cpp
index fbde930f0b..a8ad10d382 100644
--- a/lib/Sema/SemaNamedCast.cpp
+++ b/lib/Sema/SemaNamedCast.cpp
@@ -55,13 +55,13 @@ static TryStaticCastResult TryStaticImplicitCast(Sema &Self, Expr *SrcExpr,
                                                  const SourceRange &OpRange);
 
 /// ActOnCXXNamedCast - Parse {dynamic,static,reinterpret,const}_cast's.
-Action::ExprResult
+Action::OwningExprResult
 Sema::ActOnCXXNamedCast(SourceLocation OpLoc, tok::TokenKind Kind,
                         SourceLocation LAngleBracketLoc, TypeTy *Ty,
                         SourceLocation RAngleBracketLoc,
-                        SourceLocation LParenLoc, ExprTy *E,
+                        SourceLocation LParenLoc, ExprArg E,
                         SourceLocation RParenLoc) {
-  Expr *Ex = (Expr*)E;
+  Expr *Ex = (Expr*)E.release();
   QualType DestType = QualType::getFromOpaquePtr(Ty);
   SourceRange OpRange(OpLoc, RParenLoc);
   SourceRange DestRange(LAngleBracketLoc, RAngleBracketLoc);
@@ -76,29 +76,30 @@ Sema::ActOnCXXNamedCast(SourceLocation OpLoc, tok::TokenKind Kind,
   case tok::kw_const_cast:
     if (!TypeDependent)
       CheckConstCast(*this, Ex, DestType, OpRange, DestRange);
-    return new (Context) CXXConstCastExpr(DestType.getNonReferenceType(), Ex, 
-                                          DestType, OpLoc);
+    return Owned(new (Context) CXXConstCastExpr(DestType.getNonReferenceType(),
+                                                Ex, DestType, OpLoc));
 
   case tok::kw_dynamic_cast:
     if (!TypeDependent)
       CheckDynamicCast(*this, Ex, DestType, OpRange, DestRange);
-    return new (Context)CXXDynamicCastExpr(DestType.getNonReferenceType(), Ex, 
-                                           DestType, OpLoc);
+    return Owned(new (Context)CXXDynamicCastExpr(DestType.getNonReferenceType(),
+                                                 Ex, DestType, OpLoc));
 
   case tok::kw_reinterpret_cast:
     if (!TypeDependent)
       CheckReinterpretCast(*this, Ex, DestType, OpRange, DestRange);
-    return new (Context) CXXReinterpretCastExpr(DestType.getNonReferenceType(),
-                                                Ex, DestType, OpLoc);
+    return Owned(new (Context) CXXReinterpretCastExpr(
+                                  DestType.getNonReferenceType(),
+                                  Ex, DestType, OpLoc));
 
   case tok::kw_static_cast:
     if (!TypeDependent)
       CheckStaticCast(*this, Ex, DestType, OpRange);
-    return new (Context) CXXStaticCastExpr(DestType.getNonReferenceType(), Ex, 
-                                           DestType, OpLoc);
+    return Owned(new (Context) CXXStaticCastExpr(DestType.getNonReferenceType(),
+                                                 Ex, DestType, OpLoc));
   }
 
-  return true;
+  return ExprError();
 }
 
 /// CheckConstCast - Check that a const_cast\<DestType\>(SrcExpr) is valid.
diff --git a/lib/Sema/SemaTemplateInstantiate.cpp b/lib/Sema/SemaTemplateInstantiate.cpp
index 9372d33788..9126d2a262 100644
--- a/lib/Sema/SemaTemplateInstantiate.cpp
+++ b/lib/Sema/SemaTemplateInstantiate.cpp
@@ -847,16 +847,18 @@ TemplateExprInstantiator::VisitCXXTemporaryObjectExpr(
     if (Args.size() > 1)
       CommaLoc 
         = SemaRef.PP.getLocForEndOfToken(Args[0]->getSourceRange().getEnd());
-    Sema::ExprResult Result 
-      = SemaRef.ActOnCXXTypeConstructExpr(SourceRange(E->getTypeBeginLoc()
-                                                      /*, FIXME*/),
-                                          T.getAsOpaquePtr(),
-                                          /*FIXME*/E->getTypeBeginLoc(),
-                                          (void**)&Args[0], Args.size(),
-                                          /*HACK*/&CommaLoc,
-                                          E->getSourceRange().getEnd());
-    if (!Result.isInvalid())
-      return SemaRef.Owned(Result);
+    Sema::OwningExprResult Result(
+      SemaRef.ActOnCXXTypeConstructExpr(SourceRange(E->getTypeBeginLoc()
+                                                    /*, FIXME*/),
+                                        T.getAsOpaquePtr(),
+                                        /*FIXME*/E->getTypeBeginLoc(),
+                                        Sema::MultiExprArg(SemaRef,
+                                                           (void**)&Args[0],
+                                                           Args.size()),
+                                        /*HACK*/&CommaLoc,
+                                        E->getSourceRange().getEnd()));
+    // At this point, Args no longer owns the arguments, no matter what.
+    return move(Result);
   }
 
   // Clean up the instantiated arguments.