diff --git a/AST/Expr.cpp b/AST/Expr.cpp
index 620c29b..08773e8 100644
--- a/AST/Expr.cpp
+++ b/AST/Expr.cpp
@@ -15,6 +15,8 @@
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/StmtVisitor.h"
 #include "clang/Lex/IdentifierTable.h"
+// is this bad layering? I (snaroff) don't think so. Want Chris to weigh in.
+#include "clang/Parse/DeclSpec.h" 
 using namespace clang;
 
 //===----------------------------------------------------------------------===//
@@ -854,6 +856,52 @@
   return Result;
 }
 
+// constructor for unary messages.
+ObjCMessageExpr::ObjCMessageExpr(
+  IdentifierInfo *clsName, SelectorInfo &methName, QualType retType, 
+  SourceLocation LBrac, SourceLocation RBrac)
+  : Expr(ObjCMessageExprClass, retType), Selector(methName) {
+  ClassName = clsName;
+  LBracloc = LBrac;
+  RBracloc = RBrac;
+}
+
+ObjCMessageExpr::ObjCMessageExpr(
+  Expr *fn, SelectorInfo &methName, QualType retType, 
+  SourceLocation LBrac, SourceLocation RBrac)
+  : Expr(ObjCMessageExprClass, retType), Selector(methName), ClassName(0) {
+  SubExprs = new Expr*[1];
+  SubExprs[RECEIVER] = fn;
+  LBracloc = LBrac;
+  RBracloc = RBrac;
+}
+
+// constructor for keyword messages.
+ObjCMessageExpr::ObjCMessageExpr(
+  Expr *fn, SelectorInfo &selInfo, ObjcKeywordMessage *keys, unsigned numargs, 
+  QualType retType, SourceLocation LBrac, SourceLocation RBrac)
+  : Expr(ObjCMessageExprClass, retType), Selector(selInfo), ClassName(0) {
+  SubExprs = new Expr*[numargs+1];
+  SubExprs[RECEIVER] = fn;
+  for (unsigned i = 0; i != numargs; ++i)
+    SubExprs[i+ARGS_START] = static_cast<Expr *>(keys[i].KeywordExpr);
+  LBracloc = LBrac;
+  RBracloc = RBrac;
+}
+
+ObjCMessageExpr::ObjCMessageExpr(
+  IdentifierInfo *clsName, SelectorInfo &selInfo, ObjcKeywordMessage *keys, 
+  unsigned numargs, QualType retType, SourceLocation LBrac, SourceLocation RBrac)
+  : Expr(ObjCMessageExprClass, retType), Selector(selInfo), ClassName(clsName) {
+  SubExprs = new Expr*[numargs+1];
+  SubExprs[RECEIVER] = 0;
+  for (unsigned i = 0; i != numargs; ++i)
+    SubExprs[i+ARGS_START] = static_cast<Expr *>(keys[i].KeywordExpr);
+  LBracloc = LBrac;
+  RBracloc = RBrac;
+}
+
+
 //===----------------------------------------------------------------------===//
 //  Child Iterators for iterating over subexpressions/substatements
 //===----------------------------------------------------------------------===//
@@ -1023,3 +1071,11 @@
 Stmt::child_iterator ObjCEncodeExpr::child_begin() { return NULL; }
 Stmt::child_iterator ObjCEncodeExpr::child_end() { return NULL; }
 
+// ObjCMessageExpr
+Stmt::child_iterator ObjCMessageExpr::child_begin() {
+  return reinterpret_cast<Stmt**>(&SubExprs[0]);
+}
+Stmt::child_iterator ObjCMessageExpr::child_end() {
+  return reinterpret_cast<Stmt**>(&SubExprs[NumArgs+ARGS_START]);
+}
+
diff --git a/AST/StmtPrinter.cpp b/AST/StmtPrinter.cpp
index 9e8f3e9..11dd2ef 100644
--- a/AST/StmtPrinter.cpp
+++ b/AST/StmtPrinter.cpp
@@ -612,6 +612,17 @@
   OS << Node->getEncodedType().getAsString() << ")";
 }
 
+void StmtPrinter::VisitObjCMessageExpr(ObjCMessageExpr *Mess) {
+  OS << "[";
+  PrintExpr(Mess->getReceiver());
+  for (unsigned i = 0, e = Mess->getNumArgs(); i != e; ++i) {
+    // FIXME: get/print keyword...
+    PrintExpr(Mess->getArg(i));
+  }
+  OS << "]";
+}
+
+
 //===----------------------------------------------------------------------===//
 // Stmt method implementations
 //===----------------------------------------------------------------------===//
diff --git a/Parse/ParseObjc.cpp b/Parse/ParseObjc.cpp
index 224b826..356c7a7 100644
--- a/Parse/ParseObjc.cpp
+++ b/Parse/ParseObjc.cpp
@@ -1007,7 +1007,7 @@
 ///   
 Parser::ExprResult Parser::ParseObjCMessageExpression() {
   assert(Tok.getKind() == tok::l_square && "'[' expected");
-  SourceLocation Loc = ConsumeBracket(); // consume '['
+  SourceLocation LBracloc = ConsumeBracket(); // consume '['
   IdentifierInfo *ReceiverName = 0;
   ExprTy *ReceiverExpr = 0;
   // Parse receiver
@@ -1073,20 +1073,22 @@
     SkipUntil(tok::semi);
     return 0;
   }
-  ConsumeBracket(); // consume ']'
+  SourceLocation RBracloc = ConsumeBracket(); // consume ']'
   
   if (KeyInfo.size()) {
     // We've just parsed a keyword message.
     if (ReceiverName) 
       return Actions.ActOnKeywordMessage(ReceiverName, 
-                                            &KeyInfo[0], KeyInfo.size());
+                                         &KeyInfo[0], KeyInfo.size(),
+                                         LBracloc, RBracloc);
     return Actions.ActOnKeywordMessage(ReceiverExpr, 
-                                            &KeyInfo[0], KeyInfo.size());
+                                       &KeyInfo[0], KeyInfo.size(),
+                                       LBracloc, RBracloc);
   }
   // We've just parsed a unary message (a message with no arguments).
   if (ReceiverName) 
-    return Actions.ActOnUnaryMessage(ReceiverName, selIdent);
-  return Actions.ActOnUnaryMessage(ReceiverExpr, selIdent);
+    return Actions.ActOnUnaryMessage(ReceiverName, selIdent, LBracloc,RBracloc);
+  return Actions.ActOnUnaryMessage(ReceiverExpr, selIdent, LBracloc,RBracloc);
 }
 
 Parser::ExprResult Parser::ParseObjCStringLiteral() {
diff --git a/Sema/Sema.h b/Sema/Sema.h
index 79fc111..29a03d1 100644
--- a/Sema/Sema.h
+++ b/Sema/Sema.h
@@ -384,17 +384,22 @@
 		    tok::ObjCKeywordKind MethodImplKind);
                     
   // This actions handles keyword message to classes.
-  virtual ExprResult ActOnKeywordMessage(IdentifierInfo *receivingClassName, 
-    ObjcKeywordMessage *Keywords, unsigned NumKeywords);
+  virtual ExprResult ActOnKeywordMessage(
+    IdentifierInfo *receivingClassName, 
+    ObjcKeywordMessage *Keywords, unsigned NumKeywords,
+    SourceLocation lbrac, SourceLocation rbrac);
   // This action handles keyword messages to instances.
   virtual ExprResult ActOnKeywordMessage(ExprTy *receiver, 
-    ObjcKeywordMessage *Keywords, unsigned NumKeywords);
-    
-  // This actions handles keyword message to classes.
-  virtual ExprResult ActOnUnaryMessage(IdentifierInfo *receivingClassName, 
-                                    IdentifierInfo *selName);
-  // This action handles keyword messages to instances.
-  virtual ExprResult ActOnUnaryMessage(ExprTy *receiver, IdentifierInfo *sName);
+    ObjcKeywordMessage *Keywords, unsigned NumKeywords,
+    SourceLocation lbrac, SourceLocation rbrac);
+  // This actions handles unary message to classes.
+  virtual ExprResult ActOnUnaryMessage(
+    IdentifierInfo *receivingClassName, IdentifierInfo *selName,
+    SourceLocation lbrac, SourceLocation rbrac);
+  // This action handles unary messages to instances.
+  virtual ExprResult ActOnUnaryMessage(
+    ExprTy *receiver, IdentifierInfo *sName,
+    SourceLocation lbrac, SourceLocation rbrac);
 private:
   // UsualUnaryConversions - promotes integers (C99 6.3.1.1p2) and converts
   // functions and arrays to their respective pointers (C99 6.3.2.1). 
diff --git a/Sema/SemaDecl.cpp b/Sema/SemaDecl.cpp
index 3b7d8f3..d5ca796 100644
--- a/Sema/SemaDecl.cpp
+++ b/Sema/SemaDecl.cpp
@@ -23,6 +23,7 @@
 #include "clang/Basic/LangOptions.h"
 #include "clang/Basic/TargetInfo.h"
 #include "llvm/Config/config.h" 
+#include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/SmallSet.h"
 #if !defined(LLVM_ON_WIN32)
 #include <alloca.h>
@@ -1298,21 +1299,21 @@
 
   // Derive the selector name from the keyword declarations.
   int len=0;
-  char *methodName;
   for (unsigned int i = 0; i < NumKeywords; i++) {
     if (Keywords[i].SelectorName)
       len += strlen(Keywords[i].SelectorName->getName());
     len++;
   }
-  methodName = (char *) alloca (len + 1);
+  llvm::SmallString<128> methodName;
   methodName[0] = '\0';
   for (unsigned int i = 0; i < NumKeywords; i++) {
     if (Keywords[i].SelectorName)
-      strcat(methodName, Keywords[i].SelectorName->getName());
-    strcat(methodName, ":");
+      methodName += Keywords[i].SelectorName->getName();
+    methodName += ":";
   }
-  SelectorInfo &SelName = Context.getSelectorInfo(methodName, methodName+len);
-
+  methodName[len] = '\0';
+  SelectorInfo &SelName = Context.getSelectorInfo(&methodName[0], 
+                                                  &methodName[0]+len);
   llvm::SmallVector<ParmVarDecl*, 16> Params;
 
   for (unsigned i = 0; i < NumKeywords; i++) {
@@ -1332,9 +1333,9 @@
 		      		      0, -1, AttrList, MethodType == tok::minus);
   ObjcMethod->setMethodParams(&Params[0], NumKeywords);
   if (MethodDeclKind == tok::objc_optional)
-      ObjcMethod->setDeclImplementation(ObjcMethodDecl::Optional);
+    ObjcMethod->setDeclImplementation(ObjcMethodDecl::Optional);
   else
-       ObjcMethod->setDeclImplementation(ObjcMethodDecl::Required);
+    ObjcMethod->setDeclImplementation(ObjcMethodDecl::Required);
   return ObjcMethod;
 }
 
@@ -1350,9 +1351,9 @@
 			             SelName, resultDeclType, 0, -1,
                                      AttrList, MethodType == tok::minus);
   if (MethodDeclKind == tok::objc_optional)
-      ObjcMethod->setDeclImplementation(ObjcMethodDecl::Optional);
+    ObjcMethod->setDeclImplementation(ObjcMethodDecl::Optional);
   else
-       ObjcMethod->setDeclImplementation(ObjcMethodDecl::Required);
+    ObjcMethod->setDeclImplementation(ObjcMethodDecl::Required);
   return ObjcMethod;
 }
 
diff --git a/Sema/SemaExpr.cpp b/Sema/SemaExpr.cpp
index d7136a3..886b3dd 100644
--- a/Sema/SemaExpr.cpp
+++ b/Sema/SemaExpr.cpp
@@ -15,6 +15,7 @@
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/Decl.h"
 #include "clang/AST/Expr.h"
+#include "clang/Parse/DeclSpec.h" 
 #include "clang/Lex/Preprocessor.h"
 #include "clang/Lex/LiteralSupport.h"
 #include "clang/Basic/SourceManager.h"
@@ -1856,28 +1857,76 @@
   return new ObjCEncodeExpr(t, EncodedType, AtLoc, RParenLoc);
 }
 
+static SelectorInfo &DeriveSelector(ObjcKeywordMessage *Keywords, 
+                                    unsigned NumKeywords,
+                                    ASTContext &Context) {
+  // Derive the selector name from the keyword declarations.
+  int len=0;
+  for (unsigned int i = 0; i < NumKeywords; i++) {
+    if (Keywords[i].SelectorName)
+      len += strlen(Keywords[i].SelectorName->getName());
+    len++;
+  }
+  llvm::SmallString<128> methodName;
+  methodName[0] = '\0';
+  for (unsigned int i = 0; i < NumKeywords; i++) {
+    if (Keywords[i].SelectorName)
+      methodName += Keywords[i].SelectorName->getName();
+    methodName += ":";
+  }
+  methodName[len] = '\0';
+  return Context.getSelectorInfo(&methodName[0], &methodName[0]+len);
+}
+
 // This actions handles keyword message to classes.
-Sema::ExprResult Sema::ActOnKeywordMessage(IdentifierInfo *receivingClassName, 
-    ObjcKeywordMessage *Keywords, unsigned NumKeywords)
+Sema::ExprResult Sema::ActOnKeywordMessage(
+  IdentifierInfo *receivingClassName, 
+  ObjcKeywordMessage *Keywords, unsigned NumKeywords,
+  SourceLocation lbrac, SourceLocation rbrac)
 {
-  return 0;
+  SelectorInfo &SelName = DeriveSelector(Keywords, NumKeywords, Context);
+  assert(receivingClassName && "missing receiver class name");
+
+  return new ObjCMessageExpr(receivingClassName, SelName, Keywords, NumKeywords, 
+                             Context.IntTy/*FIXME*/, lbrac, rbrac);
 }
 
 // This action handles keyword messages to instances.
-Sema::ExprResult Sema::ActOnKeywordMessage(ExprTy *receiver, 
-    ObjcKeywordMessage *Keywords, unsigned NumKeywords) {
-  return 0;
+Sema::ExprResult Sema::ActOnKeywordMessage(
+  ExprTy *receiver, ObjcKeywordMessage *Keywords, unsigned NumKeywords,
+  SourceLocation lbrac, SourceLocation rbrac) {
+  SelectorInfo &SelName = DeriveSelector(Keywords, NumKeywords, Context);
+  assert(receiver && "missing receiver expression");
+  
+  Expr *RExpr = static_cast<Expr *>(receiver);
+  return new ObjCMessageExpr(RExpr, SelName, Keywords, NumKeywords, 
+                             Context.IntTy/*FIXME*/, lbrac, rbrac);
 }
     
-// This actions handles keyword message to classes.
-Sema::ExprResult Sema::ActOnUnaryMessage(IdentifierInfo *receivingClassName, 
-                                         IdentifierInfo *selName) {
-  return 0;
+// This actions handles unary message to classes.
+Sema::ExprResult Sema::ActOnUnaryMessage(
+  IdentifierInfo *receivingClassName, IdentifierInfo *selName,
+  SourceLocation lbrac, SourceLocation rbrac) {
+  assert(receivingClassName && "missing receiver class name");
+  
+  // FIXME: this should be passed in...
+  SelectorInfo &SName = Context.getSelectorInfo(
+           selName->getName(), selName->getName()+strlen(selName->getName()));
+  return new ObjCMessageExpr(receivingClassName, SName,
+                             Context.IntTy/*FIXME*/, lbrac, rbrac);
 }
 
-// This action handles keyword messages to instances.
-Sema::ExprResult Sema::ActOnUnaryMessage(ExprTy *receiver, 
-                                         IdentifierInfo *selName) {
-  return 0;
+// This action handles unary messages to instances.
+Sema::ExprResult Sema::ActOnUnaryMessage(
+  ExprTy *receiver, IdentifierInfo *selName,
+  SourceLocation lbrac, SourceLocation rbrac) {
+  assert(receiver && "missing receiver expression");
+  
+  Expr *RExpr = static_cast<Expr *>(receiver);
+  // FIXME: this should be passed in...
+  SelectorInfo &SName = Context.getSelectorInfo(
+           selName->getName(), selName->getName()+strlen(selName->getName()));
+  return new ObjCMessageExpr(RExpr, SName,
+                             Context.IntTy/*FIXME*/, lbrac, rbrac);
 }
 
diff --git a/clang.xcodeproj/project.pbxproj b/clang.xcodeproj/project.pbxproj
index efd8ad6..0bf3c3b 100644
--- a/clang.xcodeproj/project.pbxproj
+++ b/clang.xcodeproj/project.pbxproj
@@ -708,7 +708,6 @@
 		08FB7793FE84155DC02AAC07 /* Project object */ = {
 			isa = PBXProject;
 			buildConfigurationList = 1DEB923508733DC60010E9CD /* Build configuration list for PBXProject "clang" */;
-			compatibilityVersion = "Xcode 2.4";
 			hasScannedForEncodings = 1;
 			mainGroup = 08FB7794FE84155DC02AAC07 /* clang */;
 			projectDirPath = "";
diff --git a/include/clang/AST/Expr.h b/include/clang/AST/Expr.h
index ecf6eb0..84d9a79 100644
--- a/include/clang/AST/Expr.h
+++ b/include/clang/AST/Expr.h
@@ -23,6 +23,7 @@
   class IdentifierInfo;
   class Decl;
   class ASTContext;
+  struct ObjcKeywordMessage;
   
 /// Expr - This represents one expression.  Note that Expr's are subclasses of
 /// Stmt.  This allows an expression to be transparently used any place a Stmt
@@ -1058,6 +1059,70 @@
   virtual child_iterator child_end();
 };
 
+class ObjCMessageExpr : public Expr {
+  enum { RECEIVER=0, ARGS_START=1 };
+  
+  // The following 3 slots are only used for keyword messages.
+  // Adding a subclass could save us some space. For now, we keep it simple.
+  Expr **SubExprs;
+  unsigned NumArgs;
+  
+  // A unigue name for this message.
+  SelectorInfo &Selector;
+  
+  IdentifierInfo **KeyIdents;
+  
+  IdentifierInfo *ClassName;
+  
+  SourceLocation LBracloc, RBracloc;
+public:
+  // constructor for unary messages. 
+  // FIXME: clsName should be typed to ObjCInterfaceType
+  ObjCMessageExpr(IdentifierInfo *clsName, SelectorInfo &selInfo,
+                  QualType retType, SourceLocation LBrac, SourceLocation RBrac);
+  ObjCMessageExpr(Expr *receiver, SelectorInfo &selInfo,
+                  QualType retType, SourceLocation LBrac, SourceLocation RBrac);
+                  
+  // constructor for keyword messages.
+  // FIXME: clsName should be typed to ObjCInterfaceType
+  ObjCMessageExpr(IdentifierInfo *clsName, SelectorInfo &selInfo,
+                  ObjcKeywordMessage *keys, unsigned numargs, QualType retType, 
+                  SourceLocation LBrac, SourceLocation RBrac);
+  ObjCMessageExpr(Expr *receiver, SelectorInfo &selInfo,
+                  ObjcKeywordMessage *keys, unsigned numargs, QualType retType, 
+                  SourceLocation LBrac, SourceLocation RBrac);
+  ~ObjCMessageExpr() {
+    delete [] SubExprs;
+  }
+  
+  const Expr *getReceiver() const { return SubExprs[RECEIVER]; }
+  Expr *getReceiver() { return SubExprs[RECEIVER]; }
+  
+  /// getNumArgs - Return the number of actual arguments to this call.
+  ///
+  unsigned getNumArgs() const { return NumArgs; }
+  
+  /// getArg - Return the specified argument.
+  Expr *getArg(unsigned Arg) {
+    assert(Arg < NumArgs && "Arg access out of range!");
+    return SubExprs[Arg+ARGS_START];
+  }
+  const Expr *getArg(unsigned Arg) const {
+    assert(Arg < NumArgs && "Arg access out of range!");
+    return SubExprs[Arg+ARGS_START];
+  }
+  SourceRange getSourceRange() const { return SourceRange(LBracloc, RBracloc); }
+
+  static bool classof(const Stmt *T) {
+    return T->getStmtClass() == ObjCMessageExprClass;
+  }
+  static bool classof(const ObjCMessageExpr *) { return true; }
+  
+  // Iterators
+  virtual child_iterator child_begin();
+  virtual child_iterator child_end();
+};
+
 }  // end namespace clang
 
 #endif
diff --git a/include/clang/AST/StmtNodes.def b/include/clang/AST/StmtNodes.def
index 54be80e..d505312 100644
--- a/include/clang/AST/StmtNodes.def
+++ b/include/clang/AST/StmtNodes.def
@@ -80,8 +80,9 @@
 // Obj-C Expressions.
 STMT(70, ObjCStringLiteral    , Expr)
 STMT(71, ObjCEncodeExpr       , Expr)
+STMT(72, ObjCMessageExpr      , Expr)
 
-LAST_EXPR(71)
+LAST_EXPR(72)
 
 #undef STMT
 #undef FIRST_STMT
diff --git a/include/clang/Parse/Action.h b/include/clang/Parse/Action.h
index f7a7809..fab3bfe 100644
--- a/include/clang/Parse/Action.h
+++ b/include/clang/Parse/Action.h
@@ -473,22 +473,28 @@
     return 0;
   }
   // This actions handles keyword message to classes.
-  virtual ExprResult ActOnKeywordMessage(IdentifierInfo *receivingClassName, 
-    ObjcKeywordMessage *Keywords, unsigned NumKeywords) {
+  virtual ExprResult ActOnKeywordMessage(
+    IdentifierInfo *receivingClassName, 
+    ObjcKeywordMessage *Keywords, unsigned NumKeywords,
+    SourceLocation lbrac, SourceLocation rbrac) {
     return 0;
   }
   // This action handles keyword messages to instances.
   virtual ExprResult ActOnKeywordMessage(ExprTy *receiver, 
-    ObjcKeywordMessage *Keywords, unsigned NumKeywords) {
+    ObjcKeywordMessage *Keywords, unsigned NumKeywords,
+    SourceLocation lbrac, SourceLocation rbrac) {
     return 0;
   }
-  // This actions handles keyword message to classes.
-  virtual ExprResult ActOnUnaryMessage(IdentifierInfo *receivingClassName, 
-                                    IdentifierInfo *selName) {
+  // This actions handles unary message to classes.
+  virtual ExprResult ActOnUnaryMessage(
+    IdentifierInfo *receivingClassName, IdentifierInfo *selName,
+    SourceLocation lbrac, SourceLocation rbrac) {
     return 0;
   }
-  // This action handles keyword messages to instances.
-  virtual ExprResult ActOnUnaryMessage(ExprTy *receiver,IdentifierInfo *sName) {
+  // This action handles unary messages to instances.
+  virtual ExprResult ActOnUnaryMessage(
+    ExprTy *receiver, IdentifierInfo *sName,
+    SourceLocation lbrac, SourceLocation rbrac) {
     return 0;
   }
   virtual DeclTy *ObjcClassDeclaration(Scope *S, SourceLocation AtClassLoc,