--- old/src/hotspot/os/linux/os_linux.cpp	2018-12-10 01:35:59.363262564 -0500
+++ new/src/hotspot/os/linux/os_linux.cpp	2018-12-10 01:35:57.727168975 -0500
@@ -701,6 +701,8 @@
     }
   }
 
+  assert(osthread->pthread_id() != 0, "pthread_id was not set as expected");
+
   // call one more level start routine
   thread->call_run();