diff -r ad2ca2a4ab5e -r 0e5899f09dab src/share/classes/com/sun/tools/javac/util/Bits.java
--- a/src/share/classes/com/sun/tools/javac/util/Bits.java	Tue Sep 25 11:56:46 2012 +0100
+++ b/src/share/classes/com/sun/tools/javac/util/Bits.java	Tue Sep 25 13:06:58 2012 -0700
@@ -25,6 +25,8 @@
 
 package com.sun.tools.javac.util;
 
+import java.util.Arrays;
+
 /** A class for extensible, mutable bit sets.
  *
  *  <p><b>This is NOT part of any supported API.
@@ -62,9 +64,7 @@
 
     private void sizeTo(int len) {
         if (bits.length < len) {
-            int[] newbits = new int[len];
-            System.arraycopy(bits, 0, newbits, 0, bits.length);
-            bits = newbits;
+            bits = Arrays.copyOf(bits, len);
         }
     }