message: Add checks before pointer dereferencing
  This change adds checks before dereferencing a pointer returned from a
  function.
diff: @@ -210,6 +210,7 @@ ompt_data_t *__ompt_get_thread_data_internal() {
  void __ompt_thread_assign_wait_id(void *variable) {
  kmp_info_t *ti = ompt_get_thread();
  + if (ti)
  ti->th.ompt_thread_info.wait_id = (ompt_wait_id_t)(uintptr_t)variable;
  }
  @@ -432,6 +433,9 @@ int __ompt_get_task_memory_internal(void **addr, size_t *size, int blocknum) {
  return 0; // support only a single block
  kmp_info_t *thr = ompt_get_thread();
  + if (!thr)
  + return 0;
  +
  kmp_taskdata_t *taskdata = thr->th.th_current_task;
  kmp_task_t *task = KMP_TASKDATA_TO_TASK(taskdata);
  