rb_iseqw_line_trace_specify 2443 iseq.c             rb_define_method(rb_cISeq, "line_trace_specify", rb_iseqw_line_trace_specify, 2);
rb_iseqw_line_trace_specify 2446 iseq.c             (void)rb_iseqw_line_trace_specify;
rb_iseqw_line_trace_specify  111 iseq.h         VALUE rb_iseqw_line_trace_specify(VALUE iseqval, VALUE pos, VALUE set);