Switch to using a CAS loop to update the token value.
diff --git a/binding.gyp b/binding.gyp
index f6a04b2..1107f31 100644
--- a/binding.gyp
+++ b/binding.gyp
@@ -544,6 +544,7 @@
         'src/core/lib/profiling/basic_timers.c',
         'src/core/lib/profiling/stap_timers.c',
         'src/core/lib/support/alloc.c',
+        'src/core/lib/support/atm.c',
         'src/core/lib/support/avl.c',
         'src/core/lib/support/backoff.c',
         'src/core/lib/support/cmdline.c',