git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_2@32926 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
merges r32345 from trunk into ruby_1_9_2.¶
deliverly if it is main thread.
fixes [ruby-dev:44005] [Ruby 1.9 - Bug #4950]
(check signal_buff.size first)
rb_signal_buff_size() because rb_thread_t::exec_signal
is no longer available.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_2@32926 b2dd03c8-39d4-4d8f-98ff-823fe69b080e