Found the following significant warnings:
  def3.c:34:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:49:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:67:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:74:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:89:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:111:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:114:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:119:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:122:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:155:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:174:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:181:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:200:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:207:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:226:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:244:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:251:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:269:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:276:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:300:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:303:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:309:17: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:316:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:319:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:325:17: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:331:9: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:345:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:364:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:371:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:387:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:390:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:416:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:419:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:430:17: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:433:17: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:460:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:463:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:474:17: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:477:17: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:504:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:507:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:518:17: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:521:17: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:561:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:564:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:575:17: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:578:17: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:619:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:622:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:637:17: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:640:17: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:680:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:683:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:694:17: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:697:17: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:734:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:737:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:748:17: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:751:17: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:788:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:791:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:802:17: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:805:17: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:842:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:845:13: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:856:17: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
  def3.c:859:17: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
See '/home/hornik/tmp/R.check/r-devel-clang/Work/PKGS/cec2005benchmark.Rcheck/00install.out' for details.