Convert failing assertion in ll_prof.py to a warning

tools/ll_prof.py

Index: tools/ll_prof.py
diff --git a/tools/ll_prof.py b/tools/ll_prof.py
index 5c07d9165f9f89107d55ba1572d4d02600f601be..2f72a0dc9bca7875e95849506bda0c2032c91d2d 100755
--- a/tools/ll_prof.py
+++ b/tools/ll_prof.py
@@ -1,6 +1,6 @@
 #!/usr/bin/env python
 #
-# Copyright 2010 the V8 project authors. All rights reserved.
+# Copyright 2012 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
@@ -747,7 +747,8 @@ class LibraryRepo(object):
                               origin, origin_offset))
     finally:
       pipe.close()
-    assert process.wait() == 0, "Failed to objdump %s" % mmap_info.filename
+    if process.wait() != 0:
+      print "Warning: Failed to objdump %s" % mmap_info.filename
 
   def Tick(self, pc):
     for i, mmap_info in enumerate(self.infos):