* iseq.c (rb_iseq_compile_with_option): narrow down protected
  region, and check/convert/prepare arguments before setting
  base_block which needs to roll back.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@53282 b2dd03c8-39d4-4d8f-98ff-823fe69b080e