and define CONSTFUNC and PUREFUNC if available.
  Note that I don't add those options as default because
  it still shows many false-positive (it seems not to consider
  longjmp).

* vm_eval.c (stack_check): get rb_thread_t* as an argument
  to avoid duplicate call of GET_THREAD().

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@54952 b2dd03c8-39d4-4d8f-98ff-823fe69b080e