diff --git a/Driver/ASTConsumers.cpp b/Driver/ASTConsumers.cpp
index e6a1ae4..dcbe679 100644
--- a/Driver/ASTConsumers.cpp
+++ b/Driver/ASTConsumers.cpp
@@ -182,7 +182,7 @@
   // FIXME: just print original selector name!
   Out << OMD->getSelector().getName();
   
-  for (int i = 0; i < OMD->getNumParams(); i++) {
+  for (unsigned i = 0, e = OMD->getNumParams(); i != e; ++i) {
     ParmVarDecl *PDecl = OMD->getParamDecl(i);
     // FIXME: selector is missing here!    
     Out << " :(" << PDecl->getType().getAsString() << ") " << PDecl->getName(); 
diff --git a/Driver/RewriteTest.cpp b/Driver/RewriteTest.cpp
index 8d19334..d72aaf2 100644
--- a/Driver/RewriteTest.cpp
+++ b/Driver/RewriteTest.cpp
@@ -691,7 +691,7 @@
   ResultStr += " _cmd";
   
   // Method arguments.
-  for (int i = 0; i < OMD->getNumParams(); i++) {
+  for (unsigned i = 0; i < OMD->getNumParams(); i++) {
     ParmVarDecl *PDecl = OMD->getParamDecl(i);
     ResultStr += ", ";
     if (PDecl->getType()->isObjCQualifiedIdType())
@@ -2048,7 +2048,7 @@
   ArgTypes.push_back(Context->getObjCSelType());
   if (ObjCMethodDecl *mDecl = Exp->getMethodDecl()) {
     // Push any user argument types.
-    for (int i = 0; i < mDecl->getNumParams(); i++) {
+    for (unsigned i = 0; i < mDecl->getNumParams(); i++) {
       QualType t = mDecl->getParamDecl(i)->getType()->isObjCQualifiedIdType()
                      ? Context->getObjCIdType() 
                      : mDecl->getParamDecl(i)->getType();
diff --git a/include/clang/AST/DeclObjC.h b/include/clang/AST/DeclObjC.h
index 5e85f9c..290d99e 100644
--- a/include/clang/AST/DeclObjC.h
+++ b/include/clang/AST/DeclObjC.h
@@ -77,7 +77,7 @@
   /// ParamInfo - new[]'d array of pointers to VarDecls for the formal
   /// parameters of this Method.  This is null if there are no formals.  
   ParmVarDecl **ParamInfo;
-  int NumMethodParams;
+  unsigned NumMethodParams;
   
   /// List of attributes for this method declaration.
   AttributeList *MethodAttrs;
@@ -94,8 +94,7 @@
                  Decl *contextDecl,
                  AttributeList *M = 0, bool isInstance = true,
                  bool isVariadic = false,
-                 ImplementationControl impControl = None,
-                 Decl *PrevDecl = 0)
+                 ImplementationControl impControl = None)
   : Decl(ObjCMethod, beginLoc),
     IsInstance(isInstance), IsVariadic(isVariadic),
     DeclImplementation(impControl), objcDeclQualifier(OBJC_TQ_None),
@@ -131,9 +130,7 @@
   QualType getResultType() const { return MethodDeclType; }
   
   // Iterator access to formal parameters.
-  unsigned param_size() const {
-    return NumMethodParams == -1 ? 0 : NumMethodParams;
-  }
+  unsigned param_size() const { return NumMethodParams; }
   typedef ParmVarDecl **param_iterator;
   typedef ParmVarDecl * const *param_const_iterator;
   param_iterator param_begin() { return ParamInfo; }
@@ -141,8 +138,8 @@
   param_const_iterator param_begin() const { return ParamInfo; }
   param_const_iterator param_end() const { return ParamInfo+param_size(); }
   
-  int getNumParams() const { return NumMethodParams; }
-  ParmVarDecl *getParamDecl(int i) const {
+  unsigned getNumParams() const { return NumMethodParams; }
+  ParmVarDecl *getParamDecl(unsigned i) const {
     assert(i < getNumParams() && "Illegal param #");
     return ParamInfo[i];
   }  
diff --git a/lib/Sema/SemaDeclObjC.cpp b/lib/Sema/SemaDeclObjC.cpp
index a677662..4dd84d8 100644
--- a/lib/Sema/SemaDeclObjC.cpp
+++ b/lib/Sema/SemaDeclObjC.cpp
@@ -61,7 +61,7 @@
   PI.TypeInfo = Context.getObjCSelType().getAsOpaquePtr();
   ActOnParamDeclarator(PI, FnBodyScope);
   
-  for (int i = 0; i <  MDecl->getNumParams(); i++) {
+  for (unsigned i = 0, e = MDecl->getNumParams(); i != e; ++i) {
     ParmVarDecl *PDecl = MDecl->getParamDecl(i);
     PI.Ident = PDecl->getIdentifier();
     PI.IdentLoc = PDecl->getLocation(); // user vars have a real location.
@@ -613,7 +613,7 @@
   if (Method->getResultType().getCanonicalType() !=
       PrevMethod->getResultType().getCanonicalType())
     return false;
-  for (int i = 0; i < Method->getNumParams(); i++) {
+  for (unsigned i = 0, e = Method->getNumParams(); i != e; ++i) {
     ParmVarDecl *ParamDecl = Method->getParamDecl(i);
     ParmVarDecl *PrevParamDecl = PrevMethod->getParamDecl(i);
     if (ParamDecl->getCanonicalType() != PrevParamDecl->getCanonicalType())
diff --git a/lib/Sema/SemaType.cpp b/lib/Sema/SemaType.cpp
index f717b41..d4cb979 100644
--- a/lib/Sema/SemaType.cpp
+++ b/lib/Sema/SemaType.cpp
@@ -383,7 +383,7 @@
     ArgTys.push_back(Context.getObjCIdType());
   ArgTys.push_back(Context.getObjCSelType());
       
-  for (int i = 0; i <  MDecl->getNumParams(); i++) {
+  for (int i = 0, e = MDecl->getNumParams(); i != e; ++i) {
     ParmVarDecl *PDecl = MDecl->getParamDecl(i);
     QualType ArgTy = PDecl->getType();
     assert(!ArgTy.isNull() && "Couldn't parse type?");