sigsend_to_ruby_thread, install_nativethread_sighandler):
  nativethread-support on signal handler. RE-backport from 1.9.

* ruby.h (HAVE_NATIVETHREAD_KILL): ditto.

* eval.c (ruby_native_thread_kill): ditto.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_8@10502 b2dd03c8-39d4-4d8f-98ff-823fe69b080e