process.c: ensure th->interrupt lock is held when migrating
w->cond may be changed without our knowledge in waitpid_nogvl without th->interrupt_lock
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@64201 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
process.c: ensure th->interrupt lock is held when migrating
w->cond may be changed without our knowledge in waitpid_nogvl
without th->interrupt_lock
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@64201 b2dd03c8-39d4-4d8f-98ff-823fe69b080e