rb_obj_frozen_p   222 ext/objspace/objspace_dump.c     if (rb_obj_frozen_p(obj))
rb_obj_frozen_p   601 include/ruby/intern.h PUREFUNC(VALUE rb_obj_frozen_p(VALUE));
rb_obj_frozen_p  3441 object.c           rb_define_method(rb_mKernel, "frozen?", rb_obj_frozen_p, 0);