unofficial mirror of bug-gnu-emacs@gnu.org 
 help / color / mirror / code / Atom feed
From: Andrea Corallo via "Bug reports for GNU Emacs, the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
To: Eli Zaretskii <eliz@gnu.org>
Cc: larsi@gnus.org, monnier@iro.umontreal.ca, 43725@debbugs.gnu.org
Subject: bug#43725: 28.0.50; Include feature/native-comp into master
Date: Tue, 16 Feb 2021 21:13:07 +0000	[thread overview]
Message-ID: <xjf5z2rsom4.fsf@sdf.org> (raw)
In-Reply-To: <831rdjd95w.fsf@gnu.org> (Eli Zaretskii's message of "Sat, 13 Feb 2021 22:06:51 +0200")

Addressing some easy part of the review to close the day.

Eli Zaretskii <eliz@gnu.org> writes:

[...]

> This is unsafe, because a fixnum can be larger than PTRDIFF_MAX:
>
>   +static gcc_jit_lvalue *
>   +emit_mvar_lval (Lisp_Object mvar)
>   +{
>   +  Lisp_Object mvar_slot = CALL1I (comp-mvar-slot, mvar);
>   +
>   +  if (EQ (mvar_slot, Qscratch))
>   +    {
>   +      if (!comp.scratch)
>   +       comp.scratch = gcc_jit_function_new_local (comp.func,
>   +                                                  NULL,
>   +                                                  comp.lisp_obj_type,
>   +                                                  "scratch");
>   +      return comp.scratch;
>   +    }
>   +
>   +  return comp.frame[XFIXNUM (mvar_slot)];  <<<<<<<<<<<<<<<<<<<<
>   +}

Fixed by 543e6e664c

> Likewise, this is unsafe because a fixnum can be larger than INT_MAX:
>
>   +  if (!FIXNUMP (idx))
>   +    xsignal1 (Qnative_ice,
>   +             build_string ("inconsistent data relocation container"));
>   +  reloc.idx = gcc_jit_context_new_rvalue_from_int (comp.ctxt,
>   +                                                  comp.ptrdiff_type,
>   +                                                  XFIXNUM (idx)); <<<<<<<<
>
> (There are several more calls with the same problem.)

Should we never trust in C a value coming from a Lisp_Object even if is
supposed to be constructed on purpose?

> Several comparisons like this one:
>
>   +  if (val != (long) val)
>
> are IMO better written as
>
>   if (val > LONG_MAX || val < LONG_MIN)

Fixed by 72e4a22391

> Here, wouldn't it be better to have an assertion that there are no
> more than 6 elements in the list:
>
>   +  Lisp_Object arg[6];
>   +
>   +  Lisp_Object p = XCDR (insn);
>   +  ptrdiff_t i = 0;
>   +  FOR_EACH_TAIL (p)
>   +    {
>   +      if (i == sizeof (arg) / sizeof (Lisp_Object))
>   +       break;
>   +      arg[i++] = XCAR (p);
>   +    }

This way we can have insns longer than 6 operands but we don't load
them.  These are tipically comment insn we use as a debug note therefore
not relevant here (code generation).

> This is nonportable:
>
>   +  if (!noninteractive)
>   +    {
>   +      sigset_t blocked;
>   +      /* Gcc doesn't like being interrupted at all.  */
>   +      block_input ();
>   +      sigemptyset (&blocked);
>   +      sigaddset (&blocked, SIGALRM);
>   +      sigaddset (&blocked, SIGINT);
>   +#ifdef USABLE_SIGIO
>   +      sigaddset (&blocked, SIGIO);
>   +#endif
>   +      pthread_sigmask (SIG_BLOCK, &blocked, &saved_sigset); <<<<<<<<<<<
>   +      count = SPECPDL_INDEX ();
>   +      record_unwind_protect_void (restore_sigmask);
>   +    }
>
> We shouldn't use pthread_sigmask unconditionally, we should use it
> only on Posix platforms.  Can you explain why the signals here should
> be blocked?  What happens if they aren't, and a signal arrives while
> the compilation runs?  I'm asking because on MS-Windows blocking
> signals with sigaddset/sigmask doesn't really work, so the question is
> what if anything should be done here on Windows.

IIRC the compilation was crashing.  Actually we should be able to get
rid of this piece of code.  ATM we always run in a non interactive
(typically child) process compilations so this code is not exercised
anymore.

Removed by 21858596f0

> Here, 'i' could be ptrdiff_t, no need to use EMACS_INT:
>
>   +  EMACS_INT d_vec_len = XFIXNUM (Flength (comp_u->data_vec));
>   +  for (EMACS_INT i = 0; i < d_vec_len; i++)
>   +    if (!EQ (data_relocs[i],  AREF (comp_u->data_vec, i)))
>   +      return false;
>   +
>   +  d_vec_len = XFIXNUM (Flength (comp_u->data_impure_vec));
>   +  for (EMACS_INT i = 0; i < d_vec_len; i++)

Fixed by 7b676861dd

Thanks

  Andrea





  parent reply	other threads:[~2021-02-16 21:13 UTC|newest]

Thread overview: 87+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-09-30 15:44 bug#43725: 28.0.50; Include feature/native-comp into master Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-09-30 17:27 ` Lars Ingebrigtsen
2020-09-30 22:37   ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-10-01  1:34     ` Lars Ingebrigtsen
2020-10-01  7:51       ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-10-01 13:13         ` Eli Zaretskii
2020-10-01 13:40           ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-10-01 15:55           ` Lars Ingebrigtsen
2020-10-01  2:40     ` Eli Zaretskii
2020-10-02 19:39 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-10-02 19:46   ` Eli Zaretskii
2020-10-02 19:58     ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-10-03  7:27       ` Eli Zaretskii
2020-10-03 17:23         ` Lars Ingebrigtsen
2020-10-03 18:40           ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-10-06 16:39             ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-10-07  4:28               ` Lars Ingebrigtsen
2020-10-07 14:47                 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-10-09  4:20                   ` Lars Ingebrigtsen
2020-10-06 17:11         ` Stefan Monnier
2020-11-25 18:35 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-11-26 10:10   ` Lars Ingebrigtsen
2020-11-26 11:19     ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-11-26 11:28       ` Lars Ingebrigtsen
2020-11-26 12:02         ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-12-04 22:28           ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-12-06 13:13             ` Lars Ingebrigtsen
2020-11-26 14:17     ` Eli Zaretskii
2020-11-26 21:15       ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-11-27  7:16         ` Eli Zaretskii
2021-02-13 20:06           ` Eli Zaretskii
2021-02-14 20:22             ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-02-16 21:13             ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors [this message]
2021-02-17 15:18               ` Eli Zaretskii
2021-02-18 21:22                 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-02-19  8:08                   ` Eli Zaretskii
2021-02-18 20:32               ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-02-18 20:36                 ` Eli Zaretskii
2021-02-18 20:53                   ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-02-19  7:51                     ` Eli Zaretskii
2021-02-19 11:13                       ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-02-19 12:23                         ` Eli Zaretskii
2021-02-19 22:03                           ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-02-20  6:57                             ` Eli Zaretskii
2021-02-19 12:53                 ` Pip Cet
2021-02-19 13:37                   ` Eli Zaretskii
2021-02-19 14:16                     ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-02-19 14:23                       ` Pip Cet
2021-02-19 14:35                         ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-02-19 14:59                           ` Eli Zaretskii
2021-02-19 15:00                           ` Pip Cet
2021-02-19 15:11                             ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-02-19 17:33                             ` Andy Moreton
2021-02-18 21:56             ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-02-19  8:14               ` Eli Zaretskii
2021-02-18 21:58   ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-02-19  8:16     ` Eli Zaretskii
2021-02-22 20:08       ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-02-22 20:51         ` Pip Cet
2021-02-23  3:23         ` Eli Zaretskii
2021-02-26 19:31           ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-03-09 19:13             ` Eli Zaretskii
2021-03-09 19:28               ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-03-09 19:53                 ` Eli Zaretskii
2021-03-09 20:09                   ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-03-10 13:13                     ` Eli Zaretskii
2021-03-10 13:16                       ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-03-10 15:09                         ` Eli Zaretskii
2021-03-10 15:45                           ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-03-10 16:33                             ` Eli Zaretskii
2021-03-10 16:45                               ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-03-10 17:06                                 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-03-14 17:22                                   ` Eli Zaretskii
2021-03-14 19:06                                     ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-03-14 19:51                                       ` Eli Zaretskii
2021-03-14 20:00                                         ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-03-15 15:19                                           ` Eli Zaretskii
2021-03-15 15:43                                             ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-03-15 18:33                                               ` Eli Zaretskii
2021-03-15 20:00                                                 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-03-20 11:00                                                   ` Eli Zaretskii
2021-03-20 11:55                                                     ` Eli Zaretskii
2021-03-21  8:32                                                       ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-03-21  9:57                                                         ` Eli Zaretskii
2021-03-15 14:57                                         ` Eli Zaretskii
2021-05-01 18:24 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2021-05-01 19:06   ` Eli Zaretskii

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

  List information: https://www.gnu.org/software/emacs/

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=xjf5z2rsom4.fsf@sdf.org \
    --to=bug-gnu-emacs@gnu.org \
    --cc=43725@debbugs.gnu.org \
    --cc=akrl@sdf.org \
    --cc=eliz@gnu.org \
    --cc=larsi@gnus.org \
    --cc=monnier@iro.umontreal.ca \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
Code repositories for project(s) associated with this public inbox

	https://git.savannah.gnu.org/cgit/emacs.git

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).