*** old/src/share/vm/runtime/thread.cpp	Thu May 12 16:30:52 2011
--- new/src/share/vm/runtime/thread.cpp	Thu May 12 16:30:52 2011

*** 2940,2955 ****
--- 2940,2965 ----
    _log   = NULL;
    _task  = NULL;
    _queue = queue;
    _counters = counters;
    _buffer_blob = NULL;
+   _scanned_nmethod = NULL;
  
  #ifndef PRODUCT
    _ideal_graph_printer = NULL;
  #endif
  }
  
+ void CompilerThread::oops_do(OopClosure* f, CodeBlobClosure* cf) {
+   JavaThread::oops_do(f, cf);
+   if (_scanned_nmethod != NULL && cf != NULL) {
+     // Safepoints can occur when the sweeper is scanning an nmethod so
+     // process it here to make sure it isn't unloaded in the middle of
+     // a scan.
+     cf->do_code_blob(_scanned_nmethod);
+   }
+ }
  
  // ======= Threads ========
  
  // The Threads class links together all active threads, and provides
  // operations over all threads.  It is protected by its own Mutex