diff --git a/testsuites/sptests/spintrcritical16/init.c b/testsuites/sptests/spintrcritical16/init.c
index 396445509d..4d551bae79 100644
--- a/testsuites/sptests/spintrcritical16/init.c
+++ b/testsuites/sptests/spintrcritical16/init.c
@@ -52,7 +52,10 @@ rtems_timer_service_routine test_release_from_isr(
     case_hit = true;
     (void) rtems_semaphore_release( Semaphore );
   }
-  _Thread_queue_Process_timeout( Main_TCB );
+
+  if ( Main_TCB->Wait.queue != NULL ) {
+    _Thread_queue_Process_timeout( Main_TCB );
+  }
 }
 
 rtems_task Init(