<div dir="ltr">Relatedly, does this crash?<div><br></div><div><div>(parameterize ([current-input-port (open-input-string "#\\c")]) (read-eval-print-loop))</div></div><div><br></div><div style>Robby</div></div><div class="gmail_extra"> <br><br><div class="gmail_quote">On Sat, May 11, 2013 at 12:28 PM, Robby Findler <span dir="ltr"><<a href="mailto:robby@eecs.northwestern.edu" target="_blank">robby@eecs.northwestern.edu</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> <div dir="ltr">Did you try to pull out and simplify read-eval-print-loop until you can get a stand-alone program that crashes? (The impl is in racket/private/misc.rkt.)<span class="HOEnZb"><font color="#888888"><div><br>Robby</div> </font></span></div><div class="HOEnZb"><div class="h5"><div class="gmail_extra"> <br><br><div class="gmail_quote">On Sat, May 11, 2013 at 12:19 PM, Jon Zeppieri <span dir="ltr"><<a href="mailto:zeppieri@gmail.com" target="_blank">zeppieri@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> I did:<br> <br> @@ -1555,9 +1570,9 @@ typedef void (*Scheme_Invoke_Proc)(Scheme_Env<br> *env, intptr_t phase_shift,<br> <br> /* Exploit the fact that these should never be dereferenced: */<br> #ifndef FIRST_TWO_BYTES_ARE_LEGAL_ADDRESSES<br> -# define MZ_EVAL_WAITING_CONSTANT ((Scheme_Object *)0x2)<br> -# define MZ_APPLY_WAITING_CONSTANT ((Scheme_Object *)0x4)<br> -# define MZ_MULTIPLE_VALUES_CONSTANT ((Scheme_Object *)0x6)<br> +# define MZ_EVAL_WAITING_CONSTANT ((Scheme_Object *)0x4)<br> +# define MZ_APPLY_WAITING_CONSTANT ((Scheme_Object *)0x8)<br> +# define MZ_MULTIPLE_VALUES_CONSTANT ((Scheme_Object *)0xc)<br> #endif<br> <div><div><br> <br> <br> On Sat, May 11, 2013 at 1:16 PM, Matthew Flatt <<a href="mailto:mflatt@cs.utah.edu" target="_blank">mflatt@cs.utah.edu</a>> wrote:<br> > Wild guess: Did you change the pseudo-values MZ_EVAL_WAITING_CONSTANT<br> > and MZ_MULTIPLE_VALUES_CONSTANT to make sure they're not mistreated as<br> > immediates --- or that a character is not mistreated as a pseduo-value?<br> ><br> > At Sat, 11 May 2013 13:12:54 -0400, Jon Zeppieri wrote:<br> >> These all work:<br> >><br> >> -> (write #\c)<br> >> #\c<br> >> -> (print #\c)<br> >> #\c<br> >> -> (display #\c)<br> >> c<br> >><br> >> It really seems to be the case that only functions that return<br> >> characters have problems, and then, only those that return to the repo<br> >> loop. For instance:<br> >><br> >> -> (write (values #\c))<br> >> #\c<br> >> -> (values #\c)<br> >> Segmentation fault: 11<br> >><br> >><br> >> On Sat, May 11, 2013 at 11:29 AM, Matthew Flatt <<a href="mailto:mflatt@cs.utah.edu" target="_blank">mflatt@cs.utah.edu</a>> wrote:<br> >> > The last example seems to be the only one that uses `write', while the<br> >> > others implicitly use `print'.<br> >> ><br> >> > Does<br> >> ><br> >> > (write #\c)<br> >> ><br> >> > crash? How about<br> >> ><br> >> > (print #\c)<br> >> ><br> >> > ?<br> >> ><br> >> > At Fri, 10 May 2013 21:19:25 -0400, Jon Zeppieri wrote:<br> >> >> My experiment with immediately represented characters has gotten to a<br> >> >> state where a non-JIT build passes all tests, but a JIT build fails<br> >> >> (as in, segfaults) on the following program:<br> >> >><br> >> >> #\c<br> >> >><br> >> >> It also fails on:<br> >> >><br> >> >> (integer->char 99)<br> >> >><br> >> >> and:<br> >> >><br> >> >> (define (foo x) (integer->char x))<br> >> >> (foo 99)<br> >> >><br> >> >> but not on:<br> >> >><br> >> >> (define (foo x) (write (integer->char x)))<br> >> >> (foo 99)<br> >> >><br> >> >> So there seems to be a problem returning a character from a jitted<br> >> >> function back to the repl. I haven't been able to figure out where<br> >> >> this occurs, though. gdb's stack traces don't seem very useful for<br> >> >> jitted code, and I can't use Sam's disassembler, because the process<br> >> >> dies.<br> >> >><br> >> >> Any idea where to look or what debugging tools might be useful?<br> >> >><br> >> >> -Jon<br> >> >> _________________________<br> >> >> Racket Developers list:<br> >> >> <a href="http://lists.racket-lang.org/dev" target="_blank">http://lists.racket-lang.org/dev</a><br> _________________________<br> Racket Developers list:<br> <a href="http://lists.racket-lang.org/dev" target="_blank">http://lists.racket-lang.org/dev</a><br> </div></div></blockquote></div><br></div> </div></div></blockquote></div><br></div>