Define DEBUG for v8_optimized_debug=2

src/elements.cc

 // 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 774 matching lines @@
     return ElementsAccessorSubclass::CopyElementsImpl(
         from, from_start, to, from_kind, to_start, packed_size, copy_size);
   }
 
   MUST_USE_RESULT virtual MaybeObject* AddElementsToFixedArray(
       Object* receiver,
       JSObject* holder,
       FixedArray* to,
       FixedArrayBase* from) {
     int len0 = to->length();
-#ifdef DEBUG
+#ifdef ENABLE_SLOW_ASSERTS
     if (FLAG_enable_slow_asserts) {
       for (int i = 0; i < len0; i++) {
         ASSERT(!to->get(i)->IsTheHole());
       }
     }
 #endif
     if (from == NULL) {
       from = holder->elements();
     }
 
@@ skipping 1252 matching lines @@
       UNREACHABLE();
       break;
   }
 
   array->set_elements(elms);
   array->set_length(Smi::FromInt(number_of_elements));
   return array;
 }
 
 } }  // namespace v8::internal