* lib/pp.rb (object_address_group): Use Kernel#to_s to obtain the class
  name and object address.
  This fix a problem caused by %p in C generates variable length
  address.
  Reported by ko1 via IRC.



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@43387 b2dd03c8-39d4-4d8f-98ff-823fe69b080e