diff --git a/src/main/java/net/openhft/compiler/MyJavaFileManager.java b/src/main/java/net/openhft/compiler/MyJavaFileManager.java
index <HASH>..<HASH> 100644
--- a/src/main/java/net/openhft/compiler/MyJavaFileManager.java
+++ b/src/main/java/net/openhft/compiler/MyJavaFileManager.java
@@ -99,7 +99,7 @@ class MyJavaFileManager implements JavaFileManager {
         return fileManager.isSameFile(a, b);
     }
 
-    public boolean handleOption(String current, Iterator<String> remaining) {
+    public synchronized boolean handleOption(String current, Iterator<String> remaining) {
         return fileManager.handleOption(current, remaining);
     }
Fixed ConcurrentModificationException when compiling lots of method readers under Java <I>, closes #<I> (#<I>)