GNU Emacs native compiled functions (was Re: Malicious Computer Architecture)

From	Kragen Javier Sitaker <kragen@canonical.org>
Newsgroups	comp.lang.c, comp.lang.lisp, comp.emacs
Subject	GNU Emacs native compiled functions (was Re: Malicious Computer Architecture)
Followup-To	comp.emacs
Date	2026-09-03 14:37 -0300
Organization	Primarily biological and memetic
Message-ID	<87v78mz15a.fsf_-_@debian> (permalink)
References	(9 earlier) <114piou$14lmv$2@dont-email.me> <114pno3$16g53$1@dont-email.me> <114pqg5$17lne$1@dont-email.me> <5T_bS.71191$4Fu9.56234@fx05.ams4> <27248.58134.739884.512819@parhasard.net>

Cross-posted to 3 groups.

Followups directed to: comp.emacs

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Aidan Kehoe <kehoea@parhasard.net> writes:
> I haven’t gone into the weeds of the GNU Emacs native-compiled function
> implementation, but it has to be doing something similar. The functions are not
> in the data segment, they’re not in BSS, they’re not on the stack; that leaves
> the heap.

On amd64, at least, instead of running them from a heap, it seems to be
compiling elisp into .so files which it can then dlopen(), but it names
them `*.eln` instead of `*.so`:

    : ~; shuf -n 8 /proc/$(pidof emacs)/maps
    7f44e7cb3000-7f44e7cb4000 r--p 00005000 fe:01 1216485                    /usr/lib/x86_64-linux-gnu/libgpm.so.2
    7f44e8e34000-7f44e8e47000 r--p 00000000 fe:01 1212779                    /usr/lib/x86_64-linux-gnu/libpango-1.0.so.0.5000.12
    7f44c4151000-7f44c4154000 rw-p 00005000 fe:05 1323730                    /home/user/.emacs.d/eln-cache/28.2-66fa0d00/nxml-parse-79a53381-b87f8800.eln
    7f44c74a5000-7f44c74bb000 rw-p 00006000 fe:05 1320433                    /home/user/.emacs.d/eln-cache/28.2-66fa0d00/cc-vars-6cc3f0fc-a4ab31d9.eln
    7f44c544e000-7f44c5458000 rw-p 0000b000 fe:05 1323563                    /home/user/.emacs.d/eln-cache/28.2-66fa0d00/with-editor-ad819b7b-2e1f7b93.eln
    7f44c5383000-7f44c5384000 r--p 0000d000 fe:05 1321666                    /home/user/.emacs.d/eln-cache/28.2-66fa0d00/log-edit-bc58b2d4-860d5c35.eln
    7f44c52f5000-7f44c52f8000 r--p 00021000 fe:05 1323613                    /home/user/.emacs.d/eln-cache/28.2-66fa0d00/magit-log-ffefa368-c52fff03.eln
    7f44c50a5000-7f44c50a8000 r-xp 00001000 fe:05 1321734                    /home/user/.emacs.d/eln-cache/28.2-66fa0d00/xdg-9947111f-70cd76a9.eln
    : ~; file /home/user/.emacs.d/eln-cache/28.2-66fa0d00/nxml-parse-79a53381-b87f8800.eln /home/user/.emacs.d/eln-cache/28.2-66fa0d00/cc-vars-6cc3f0fc-a4ab31d9.eln /home/user/.emacs.d/eln-cache/28.2-66fa0d00/with-editor-ad819b7b-2e1f7b93.eln
    /home/user/.emacs.d/eln-cache/28.2-66fa0d00/nxml-parse-79a53381-b87f8800.eln:  ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, BuildID[sha1]=ae37239bb67ec11b5d1eaf514df0660634fbd946, not stripped
    /home/user/.emacs.d/eln-cache/28.2-66fa0d00/cc-vars-6cc3f0fc-a4ab31d9.eln:     ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, BuildID[sha1]=043e590c8a3917994270925abbfa6ec746488abb, not stripped
    /home/user/.emacs.d/eln-cache/28.2-66fa0d00/with-editor-ad819b7b-2e1f7b93.eln: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, BuildID[sha1]=2bfb93008822275a66cad1c463d286f366388725, not stripped
    : ~; 

When I’ve disassembled these, they seem to indirect all their function
calls through a jump table, so that you can rebind existing symbols to
new functions and affect already-compiled code.  I haven’t dug into it
in much detail, though, so I might be mistaken.

Kragen

Thread

Malicious Computer Architecture (was: Re: Prioritize Performance over Correctness) Johann 'Myrkraverk' Oskarsson <johann@myrkraverk.invalid> - 2026-08-03 19:23 +0800
  Re: Malicious Computer Architecture (was: Re: Prioritize Performance over Correctness) scott@slp53.sl.home (Scott Lurndal) - 2026-08-03 14:29 +0000
    Re: Malicious Computer Architecture Kragen Javier Sitaker <kragen@canonical.org> - 2026-09-03 14:26 -0300
  Johnny Depp prevention [Windows 11 etc...] (Was: Malicious Computer Architecture) Mild Shock <janburse@fastmail.fm> - 2026-08-03 18:10 +0200
    But how can you deploy. when its ROM? (Was: Johnny Depp prevention [Windows 11 etc...]) Mild Shock <janburse@fastmail.fm> - 2026-08-03 18:15 +0200
      GPU Elasticity: Collective Communications Libraries (Was: But how can you deploy. when its ROM?) Mild Shock <janburse@fastmail.fm> - 2026-08-07 14:37 +0200
        What are Flits and Phits? [Network on a Chip] (Re: GPU Elasticity: Collective Communications Libraries) Mild Shock <janburse@fastmail.fm> - 2026-08-07 18:07 +0200
          Cristallina: Thank you for the Beam (Re: What are Flits and Phits? [Network on a Chip]) Mild Shock <janburse@fastmail.fm> - 2026-08-09 21:22 +0200
            Loderunner Enemy AI better than SWI-Prolog? [Prolog Education Group] Mild Shock <janburse@fastmail.fm> - 2026-08-18 16:26 +0200
              How to shoot yourself in the foot (Re: Loderunner Enemy AI better than SWI-Prolog? [Prolog Education Group] Mild Shock <janburse@fastmail.fm> - 2026-08-18 16:50 +0200
                Re: How to shoot yourself in the foot (Re: Loderunner Enemy AI better than SWI-Prolog? [Prolog Education Group] Johann 'Myrkraverk' Oskarsson <johann@myrkraverk.invalid> - 2026-08-19 03:24 +0800
              Re: Loderunner Enemy AI better than SWI-Prolog? [Prolog Education Group] Johann 'Myrkraverk' Oskarsson <johann@myrkraverk.invalid> - 2026-08-19 03:21 +0800
                Re: Loderunner Enemy AI better than SWI-Prolog? [Prolog Education Group] Aidan Kehoe <kehoea@parhasard.net> - 2026-08-18 21:13 +0100
                Re: Loderunner Enemy AI better than SWI-Prolog? [Prolog Education Group] Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-08-18 22:49 +0000
                Re: Loderunner Enemy AI better than SWI-Prolog? [Prolog Education Group] Johann 'Myrkraverk' Oskarsson <johann@myrkraverk.invalid> - 2026-08-19 08:32 +0800
                Re: Loderunner Enemy AI better than SWI-Prolog? [Prolog Education Group] Anthk GM <anthk@disroot.org> - 2026-09-15 17:10 +0000
                Re: Loderunner Enemy AI better than SWI-Prolog? [Prolog Education Group] scott@slp53.sl.home (Scott Lurndal) - 2026-09-15 18:08 +0000
                You hear some noises in the distance (Was: Loderunner Enemy AI better than SWI-Prolog?) Mild Shock <janburse@fastmail.fm> - 2026-09-15 20:21 +0200
                Re: You hear some noises in the distance (Was: Loderunner Enemy AI better than SWI-Prolog?) scott@slp53.sl.home (Scott Lurndal) - 2026-09-15 20:05 +0000
                Re: Loderunner Enemy AI better than SWI-Prolog? [Prolog Education Group] George Neuner <gneuner2@comcast.net> - 2026-08-21 02:08 -0400
                Re: Loderunner Enemy AI better than SWI-Prolog? [Prolog Education Group] Johann 'Myrkraverk' Oskarsson <johann@myrkraverk.invalid> - 2026-08-21 15:25 +0800
                Re: Loderunner Enemy AI better than SWI-Prolog? [Prolog Education Group] George Neuner <gneuner2@comcast.net> - 2026-08-21 16:28 -0400
                Re: Loderunner Enemy AI better than SWI-Prolog? [Prolog Education Group] Johann 'Myrkraverk' Oskarsson <johann@myrkraverk.invalid> - 2026-08-19 08:27 +0800
              William A. Howard solved all his 99 problems (Re: Loderunner Enemy AI better than SWI-Prolog?) Mild Shock <janburse@fastmail.fm> - 2026-08-23 01:48 +0200
          The Mac Neo is a Budget Monster [GPU Channels] (Re: What are Flits and Phits? [Network on a Chip]) Mild Shock <janburse@fastmail.fm> - 2026-08-11 16:27 +0200
            The luminaries of duct-tape engineering [Sweeney and Torvald] (Was: The Mac Neo is a Budget Monster [GPU Channels]) Mild Shock <janburse@fastmail.fm> - 2026-08-11 16:51 +0200
  Re: Malicious Computer Architecture Aidan Kehoe <kehoea@parhasard.net> - 2026-08-03 19:51 +0100
    Re: Malicious Computer Architecture Johann 'Myrkraverk' Oskarsson <johann@myrkraverk.invalid> - 2026-08-05 00:22 +0800
      Re: Malicious Computer Architecture Richard Harnden <richard.nospam@gmail.invalid> - 2026-08-04 19:10 +0100
      Re: Malicious Computer Architecture Kaz Kylheku <046-301-5902@kylheku.com> - 2026-08-06 21:55 +0000
        Re: Malicious Computer Architecture Johann 'Myrkraverk' Oskarsson <johann@myrkraverk.invalid> - 2026-08-07 06:31 +0800
      Re: Malicious Computer Architecture Aidan Kehoe <kehoea@parhasard.net> - 2026-08-06 23:01 +0100
        Re: Malicious Computer Architecture Johann 'Myrkraverk' Oskarsson <johann@myrkraverk.invalid> - 2026-08-07 06:45 +0800
    Re: Malicious Computer Architecture Niocláisín Cóilín de Ghlostéir <thanks-to@Taf.com> - 2026-08-04 18:13 +0000
      Re: Malicious Computer Architecture Johann 'Myrkraverk' Oskarsson <johann@myrkraverk.invalid> - 2026-08-05 03:48 +0800
        Re: Malicious Computer Architecture Niocláisín Cóilín de Ghlostéir <thanks-to@Taf.com> - 2026-08-04 22:01 +0000
          Re: Malicious Computer Architecture Johann 'Myrkraverk' Oskarsson <johann@myrkraverk.invalid> - 2026-08-05 06:25 +0800
    GNU Emacs native compiled functions (was Re: Malicious Computer Architecture) Kragen Javier Sitaker <kragen@canonical.org> - 2026-09-03 14:37 -0300
      Re: GNU Emacs native compiled functions (was Re: Malicious Computer Architecture) Madhu <enometh@meer.net> - 2026-09-04 08:36 +0530
        Re: GNU Emacs native compiled functions (was Re: Malicious Computer Architecture) Kragen Javier Sitaker <kragen@canonical.org> - 2026-09-15 12:19 -0300
          Re: GNU Emacs native compiled functions (was Re: Malicious Computer Architecture) Madhu <enometh@meer.net> - 2026-09-17 12:17 +0530
            Re: GNU Emacs native compiled functions Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-09-17 21:12 +0000
              Re: GNU Emacs native compiled functions Stefan Monnier <monnier@iro.umontreal.ca> - 2026-09-18 09:59 -0400
                Re: GNU Emacs native compiled functions Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-09-18 22:00 +0000
            Re: GNU Emacs native compiled functions (was Re: Malicious Computer Architecture) Stefan Monnier <monnier@iro.umontreal.ca> - 2026-09-18 10:12 -0400
              Re: GNU Emacs native compiled functions (was Re: Malicious Computer Architecture) Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-09-18 22:01 +0000
                Re: GNU Emacs native compiled functions (was Re: Malicious Computer Architecture) steve g <Sgonedes1977@gmail.com> - 2026-10-05 19:30 -0400
                Re: GNU Emacs native compiled functions (was Re: Malicious Computer Architecture) Kaz Kylheku <046-301-5902@kylheku.com> - 2026-10-05 23:50 +0000
                Re: GNU Emacs native compiled functions (was Re: Malicious Computer Architecture) tfb <tfb@work.it.out> - 2026-10-06 05:11 +0000
              Re: GNU Emacs native compiled functions Aidan Kehoe <kehoea@parhasard.net> - 2026-09-19 14:47 +0100
                Re: GNU Emacs native compiled functions Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-09-19 21:58 +0000
                Re: GNU Emacs native compiled functions Aidan Kehoe <kehoea@parhasard.net> - 2026-09-19 23:24 +0100
                Re: GNU Emacs native compiled functions Paul Rubin <no.email@nospam.invalid> - 2026-09-19 17:23 -0700
                Re: GNU Emacs native compiled functions Stefan Monnier <monnier@iro.umontreal.ca> - 2026-09-20 03:05 -0400
                Re: GNU Emacs native compiled functions Kaz Kylheku <046-301-5902@kylheku.com> - 2026-09-22 18:20 +0000
                Re: GNU Emacs native compiled functions Aidan Kehoe <kehoea@parhasard.net> - 2026-09-20 22:20 +0100
                Re: GNU Emacs native compiled functions Paul Rubin <no.email@nospam.invalid> - 2026-09-20 16:18 -0700
                Re: GNU Emacs native compiled functions Stefan Monnier <monnier@iro.umontreal.ca> - 2026-09-21 12:56 -0400
                Re: GNU Emacs native compiled functions Madhu <enometh@meer.net> - 2026-09-22 12:22 +0530
                Re: GNU Emacs native compiled functions Paul Rubin <no.email@nospam.invalid> - 2026-09-22 10:15 -0700
                Re: GNU Emacs native compiled functions Madhu <enometh@meer.net> - 2026-09-23 07:33 +0530
                Re: GNU Emacs native compiled functions Aidan Kehoe <kehoea@parhasard.net> - 2026-09-23 07:22 +0100
                Re: GNU Emacs native compiled functions Paul Rubin <no.email@nospam.invalid> - 2026-09-24 03:06 -0700
                Re: GNU Emacs native compiled functions Lars Brinkhoff <lars.spam@nocrew.org> - 2026-09-26 04:45 +0000
                Re: GNU Emacs native compiled functions Madhu <enometh@meer.net> - 2026-09-27 16:24 +0530
                Re: GNU Emacs native compiled functions Paul Rubin <no.email@nospam.invalid> - 2026-09-27 15:02 -0700
                Re: GNU Emacs native compiled functions Madhu <enometh@meer.net> - 2026-09-28 10:53 +0530
                Re: GNU Emacs native compiled functions steve g <Sgonedes1977@gmail.com> - 2026-10-05 19:47 -0400
                Re: GNU Emacs native compiled functions Anton Antimo <anton@safunu.org> - 2026-09-24 10:25 -0300
                Re: GNU Emacs native compiled functions steve g <Sgonedes1977@gmail.com> - 2026-10-05 19:49 -0400
                Re: GNU Emacs native compiled functions Lars Brinkhoff <lars.spam@nocrew.org> - 2026-09-23 13:59 +0000
                Re: GNU Emacs native compiled functions Kaz Kylheku <046-301-5902@kylheku.com> - 2026-09-22 18:22 +0000
                Re: GNU Emacs native compiled functions tfb <tfb@work.it.out> - 2026-09-24 20:01 +0000
                Re: GNU Emacs native compiled functions Kaz Kylheku <046-301-5902@kylheku.com> - 2026-09-24 20:55 +0000
                Re: GNU Emacs native compiled functions steve g <Sgonedes1977@gmail.com> - 2026-10-05 19:41 -0400
                Re: GNU Emacs native compiled functions Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-09-21 00:18 +0000
                Re: GNU Emacs native compiled functions antispam@fricas.org (Waldek Hebisch) - 2026-09-21 19:06 +0000
                Re: GNU Emacs native compiled functions Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-09-22 00:42 +0000
                Re: GNU Emacs native compiled functions Kaz Kylheku <046-301-5902@kylheku.com> - 2026-09-22 18:26 +0000
                Re: GNU Emacs native compiled functions antispam@fricas.org (Waldek Hebisch) - 2026-09-25 21:54 +0000
                Re: GNU Emacs native compiled functions steve g <Sgonedes1977@gmail.com> - 2026-10-05 20:13 -0400
                Re: GNU Emacs native compiled functions Kaz Kylheku <046-301-5902@kylheku.com> - 2026-09-22 17:51 +0000
              Re: GNU Emacs native compiled functions (was Re: Malicious Computer Architecture) Kaz Kylheku <046-301-5902@kylheku.com> - 2026-09-22 18:02 +0000
  A Case for Impurity: The Applied Pi Calculus (Re: Malicious Computer Architecture) Mild Shock <janburse@fastmail.fm> - 2026-08-04 14:58 +0200
    The Sandcastle of Paul Taraus Interactors (Re: A Case for Impurity: The Applied Pi Calculus) Mild Shock <janburse@fastmail.fm> - 2026-08-04 15:10 +0200

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