Hello, Sergey Bugaev, le dim. 02 avril 2023 15:22:33 +0300, a ecrit: > I propose the following: before resetting the exception port, glibc > would fetch the previous one, and if it's non-null, it will perform a > special synchronous RPC on it, both passing the new exception port > that it would set to the tracer (so there's no need to actually set > it), and telling the tracer what its signal thread is (currently GDB > just tries to guess that the second thread is the one, except this > again doesn't work for the very same reason, there's not yet a second > thread when the task is at its very _start). > > routine name_to_be_bikeshedded ( > tracer_exc_port: mach_port_move_send_t; > my_exc_port: mach_port_make_send_t; > signal_thread: thread_t);
Yes, that seems much more cooperative. I would say call it exception_set_exception_port? > Any ideas how to fix the first issue (thread and subcode info getting > lost when forwarding signals to the tracer)? I'd say just add an extended proc_wait RPC indeed. proc can easily implement both, and new callers can revert to the old version. Samuel
