Fix some build warnings in Nacl-specific code

lib/Analysis/NaCl/PNaClABITypeChecker.cpp

 //===- PNaClABICheckTypes.h - Verify PNaCl ABI rules --------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // Common type-checking code for module and function-level passes
 //
 //
 //===----------------------------------------------------------------------===//
 
 #include "PNaClABITypeChecker.h"
 #include "llvm/IR/Constant.h"
 #include "llvm/IR/Constants.h"
 #include "llvm/IR/DerivedTypes.h"
 #include "llvm/IR/Metadata.h"
 
 using namespace llvm;
 
 bool PNaClABITypeChecker::isValidType(const Type *Ty) {
   if (VisitedTypes.count(Ty))
     return VisitedTypes[Ty];
 
-  unsigned Width;

[Derek Schuff, 2013/05/14 18:40:04]

this is used by the commented-out block in case Type::IntegerTyID below, and
will shortly be used. If you want to suppress the warning for now, just comment
it out too.

[eliben, 2013/05/14 19:23:38]

Done.

   bool Valid = false;
   switch (Ty->getTypeID()) {
     // Allowed primitive types
     case Type::VoidTyID:
     case Type::FloatTyID:
     case Type::DoubleTyID:
     case Type::LabelTyID:
     case Type::MetadataTyID:
       Valid = true;
       break;
@@ skipping 89 matching lines @@
   for (unsigned i = 0, e = N->getNumOperands(); i != e; i++) {
     if (Value *Op = N->getOperand(i)) {
       if (Type *Invalid = checkTypesInConstant(dyn_cast<Constant>(Op))) {
         VisitedConstants[N] = Invalid;
         return Invalid;
       }
     }
   }
   return NULL;
 }