* vm_method.c (rb_gc_mark_unlinked_live_method_entries):
  revert last commit to introduce debug prints.



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@43262 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* class.c, variable.c, gc.c (rb_class_tbl): removed.
* vm.c, vm_core.h (rb_vm_add_root_module): added to register as a
  defined root module or class.
  This guard helps mark miss from defined classes/modules they are
  only refered from C's global variables in C-exts.
  Basically, it is extension's bug.
  Register to hash object VM has.
  Marking a hash objects allows generational GC supports.
* gc.c (RGENGC_PRINT_TICK): disable (revert).



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@43263 b2dd03c8-39d4-4d8f-98ff-823fe69b080e