New attempt to make the allocation routines 64 bit clean....

test/cctest/test-spaces.cc

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 203 matching lines @@
   HeapObject* ho = HeapObject::cast(obj);
   ho->set_map(faked_map);
 
   CHECK(lo->Contains(HeapObject::cast(obj)));
 
   CHECK(lo->FindObject(ho->address()) == obj);
 
   CHECK(lo->Contains(ho));
 
   while (true) {
-    int available = lo->Available();
+    intptr_t available = lo->Available();
     obj = lo->AllocateRaw(lo_size);
     if (obj->IsFailure()) break;
     HeapObject::cast(obj)->set_map(faked_map);
     CHECK(lo->Available() < available);
   };
 
   CHECK(!lo->IsEmpty());
 
   obj = lo->AllocateRaw(lo_size);
   CHECK(obj->IsFailure());
 
   lo->TearDown();
   delete lo;
 
   MemoryAllocator::TearDown();
 }