Fix building with GCC 3.x

src/heap.h

 // Copyright 2012 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 1136 matching lines @@
   // The hidden_symbol is special because it is the empty string, but does
   // not match the empty string.
   String* hidden_symbol() { return hidden_symbol_; }
 
   void set_global_contexts_list(Object* object) {
     global_contexts_list_ = object;
   }
   Object* global_contexts_list() { return global_contexts_list_; }
 
   // Number of mark-sweeps.
-  int ms_count() { return ms_count_; }
+  unsigned int ms_count() { return ms_count_; }
 
   // Iterates over all roots in the heap.
   void IterateRoots(ObjectVisitor* v, VisitMode mode);
   // Iterates over all strong roots in the heap.
   void IterateStrongRoots(ObjectVisitor* v, VisitMode mode);
   // Iterates over all the other roots in the heap.
   void IterateWeakRoots(ObjectVisitor* v, VisitMode mode);
 
   // Iterate pointers to from semispace of new space found in memory interval
   // from start to end.
@@ skipping 523 matching lines @@
   OldSpace* code_space_;
   MapSpace* map_space_;
   CellSpace* cell_space_;
   LargeObjectSpace* lo_space_;
   HeapState gc_state_;
   int gc_post_processing_depth_;
 
   // Returns the amount of external memory registered since last global gc.
   intptr_t PromotedExternalMemorySize();
 
-  int ms_count_;  // how many mark-sweep collections happened
+  unsigned int ms_count_;  // how many mark-sweep collections happened
   unsigned int gc_count_;  // how many gc happened
 
   // For post mortem debugging.
   static const int kRememberedUnmappedPages = 128;
   int remembered_unmapped_pages_index_;
   Address remembered_unmapped_pages_[kRememberedUnmappedPages];
 
   // Total length of the strings we failed to flatten since the last GC.
   int unflattened_strings_length_;
 
@@ skipping 1046 matching lines @@
   AssertNoAllocation no_alloc;  // i.e. no gc allowed.
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(PathTracer);
 };
 #endif  // DEBUG || LIVE_OBJECT_LIST
 
 } }  // namespace v8::internal
 
 #endif  // V8_HEAP_H_