rb_st_copy        338 class.c        	RCLASS_IV_TBL(clone) = rb_st_copy(clone, RCLASS_IV_TBL(orig));
rb_st_copy        391 class.c        	    RCLASS_IV_TBL(clone) = rb_st_copy(clone, RCLASS_IV_TBL(klass));
rb_st_copy       1599 internal.h     st_table *rb_st_copy(VALUE obj, struct st_table *orig_tbl);