diff -r f9c4371d59d4 -r 7721042bdb67 src/ObjectVisitor.h
--- a/src/ObjectVisitor.h	Thu Dec 27 21:07:03 2012 -0800
+++ b/src/ObjectVisitor.h	Fri Dec 28 17:13:51 2012 -0800
@@ -148,6 +148,11 @@
         return array->objSize(map);
     }
 
+    size_t iterateDependentArray(Object *array) {
+        visitField(array, DependentArray::offsetOfRoot());
+        return sizeof(DependentArray);
+    }
+
     size_t iterateBox(Box *obj) {
         visitField(obj, Box::offsetOfType());
         if (obj->type()->isTraceable())
@@ -248,7 +253,10 @@
             return iterateString(obj);
 
           case MapKind_Array:
-            return Align(iterateArray(Array::cast(obj), ArrayMap::cast(map)), kObjectAlignment);
+            return iterateArray(Array::cast(obj), ArrayMap::cast(map));
+
+          case MapKind_DependentArray:
+            return iterateDependentArray(obj);
 
           case MapKind_Box:
             return iterateBox(Box::cast(obj));
@@ -340,7 +348,10 @@
         return sizeof(Native);
 
       case MapKind_Array:
-        return Align(Array::cast(obj)->objSize(ArrayMap::cast(map)), kObjectAlignment);
+        return Array::cast(obj)->objSize(ArrayMap::cast(map));
+
+       case MapKind_DependentArray:
+        return sizeof(DependentArray), kObjectAlignment;
 
       case MapKind_Box:
         return sizeof(Box);