* gc.c (lazy_sweep): Use is_lazy_sweeping()
	* gc.c (rest_sweep): Ditto.
	* gc.c (gc_prepare_free_objects): Ditto.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@41510 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* gc.c: fix to support USE_RGENGC == 0 (disable RGenGC).
  If USE_RGENGC==0, it caused compilation error.



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@41511 b2dd03c8-39d4-4d8f-98ff-823fe69b080e