--- a/langtools/src/share/classes/com/sun/tools/javac/code/Flags.java	Wed Mar 02 21:06:17 2011 -0800
+++ b/langtools/src/share/classes/com/sun/tools/javac/code/Flags.java	Wed Mar 02 21:13:55 2011 -0800
@@ -43,7 +43,7 @@
     private Flags() {} // uninstantiable
 
     public static String toString(long flags) {
-        StringBuffer buf = new StringBuffer();
+        StringBuilder buf = new StringBuilder();
         String sep = "";
         for (Flag s : asFlagSet(flags)) {
             buf.append(sep);