git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@28771 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* configure.in (cbrt): check for replacement functions. * missing/cbrt.c: new file. git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@15416 b2dd03c8-39d4-4d8f-98ff-823fe69b080e