* thread.c (TIMEVAL_SEC_MAX, TIMEVAL_SEC_MIN): Consider environments,
  sizeof(time_t) is smaller than sizeof(tv_sec), such as
  OpenBSD 5.2 (amd64).


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@40492 b2dd03c8-39d4-4d8f-98ff-823fe69b080e