message: DVLOG: don't do anything if NDEBUG is defined.
diff: @@ -39,7 +39,11 @@ extern int global_vlog_level_;
  #define VLOG_IS_ON(x) (::verible::global_vlog_level_ >= (x))
  #endif
  #define VLOG(x) LOG_IF(INFO, VLOG_IS_ON(x))
  +#ifdef NDEBUG
  +#define DVLOG(x) LOG_IF(INFO, false)
  +#else
  #define DVLOG(x) VLOG(x)
  +#endif
  #define CHECK_NOTNULL(p) (void)ABSL_DIE_IF_NULL(p)
  