argument and prevent coredump when a nonexistent key is
specified.
* ext/sdbm/init.c (fsdbm_indexes, fsdbm_select): ditto.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_6@2999 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* eval.c (rb_thread_schedule): inifinite sleep should not cause
dead lock.
* array.c (rb_ary_flatten_bang): proper recursive detection.
* eval.c (yield_under): need not to prohibit at safe leve 4.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_6@1353 b2dd03c8-39d4-4d8f-98ff-823fe69b080e