From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Pip Cet Newsgroups: gmane.emacs.bugs Subject: bug#32463: 27.0.50; (logior -1) => 4611686018427387903 Date: Sun, 19 Aug 2018 10:48:19 +0000 Message-ID: References: <5230a57b-5896-606d-f157-2e547710b6e8@cs.ucla.edu> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" X-Trace: blaine.gmane.org 1534675691 24759 195.159.176.226 (19 Aug 2018 10:48:11 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Sun, 19 Aug 2018 10:48:11 +0000 (UTC) Cc: andrewjmoreton@gmail.com, 32463@debbugs.gnu.org To: eggert@cs.ucla.edu Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Sun Aug 19 12:48:06 2018 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1frLFe-0006Kf-D1 for geb-bug-gnu-emacs@m.gmane.org; Sun, 19 Aug 2018 12:48:06 +0200 Original-Received: from localhost ([::1]:42367 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1frLHk-0001Pk-Ng for geb-bug-gnu-emacs@m.gmane.org; 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Sun, 19 Aug 2018 10:50:02 +0000 Original-Received: (at 32463) by debbugs.gnu.org; 19 Aug 2018 10:49:06 +0000 Original-Received: from localhost ([127.0.0.1]:54408 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1frLGa-0000wD-I1 for submit@debbugs.gnu.org; Sun, 19 Aug 2018 06:49:05 -0400 Original-Received: from mail-lj1-f181.google.com ([209.85.208.181]:43455) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1frLGZ-0000vH-4e for 32463@debbugs.gnu.org; Sun, 19 Aug 2018 06:49:03 -0400 Original-Received: by mail-lj1-f181.google.com with SMTP id r13-v6so9444309ljg.10 for <32463@debbugs.gnu.org>; Sun, 19 Aug 2018 03:49:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=Jx0AlwvHOqXLMq/guzGydQ56nHmx4QnSS0FjQ6IBXyk=; b=C6UoriKo7KqIEwUfVJUdM5WEmEYFxqmgQLe0bUKNDnpJ5/iouMm9rdM9yvql6iet2F SImezPJZkQzQzJnUQYwQhhIOje5AAi2+0zpc4vTr3OUFztd+ff6poOXs6TvA/n0BgTsy 7yc+oPMsQcPQqviMQGokUFaTcaKqHHO3BcOt2cUdshIARPmHtbk6lKsubE8e3xUoM77p JDuVMz+WpotNnR/QUjWLPaJdKcOkogF9zzyHcMaHnsS+t6uJH0NJrrEjjaXQ6amsz0O/ 2LvREZps0PpU3O2NITuji7ijFl69i/YD9iMdc3phb3x+sUHWwVLwvGLjDE5oJ4kKTuVd +30Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=Jx0AlwvHOqXLMq/guzGydQ56nHmx4QnSS0FjQ6IBXyk=; b=cU8QWUGe427hAPrOcBDoYTZ4M1Tras6sTqKcYEiRGHEjUdC6Kwz5SexxLDw63vH740 BSBQa7CAWTc46jqaBCczwvqLIOvU5Q31znIBH2HPW5Yng/fdzFKwie70PSwvdd/iODLW AeLF2muzcrI5k7/LPVL4Wuert1mQjqA+3Hk8bU5W8FM7wNRfzWabdD3s1vfOhNMhzxLm 1BZzcFQdRUXo4zvtrYkxOQ7zCGKHt6jjm1hk72AmyxKSa6TE0mx7FjvO1Ie2xZub68Oj smoZZM9ojkIpAp9JxH/+IezEs9OnjWS8FRYeEKBoCCXrw9HIidlyve199cevMG6rdBfU aOmg== X-Gm-Message-State: AOUpUlEdhNKy5KYvrEJDtUd+uP853olYkO2ZXEg4E8jpaQQWMTxu2fzm HsZgvFXYbZGG62UH2DIh+8r8h8vitwjkBT59cs0= X-Google-Smtp-Source: AA+uWPzi8lni1/0tx6wcgVozKpNPqLw1YzRjXeTbx+45iy6GUz8pq6D7BE7XVqb3TER7KGefeSPZ0HJ1HATSMGBhwzQ= X-Received: by 2002:a2e:5243:: with SMTP id g64-v6mr27945281ljb.144.1534675737366; Sun, 19 Aug 2018 03:48:57 -0700 (PDT) In-Reply-To: <5230a57b-5896-606d-f157-2e547710b6e8@cs.ucla.edu> X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 208.118.235.43 X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.org gmane.emacs.bugs:149589 Archived-At: On Sat, Aug 18, 2018 at 10:58 PM Paul Eggert wrote: My bigger concern is memory management, along with integer overflow in size or > bitcount calculation. Copies are made of bignums when not needed, behavior is > dicey if memory is exhausted during bignum computation, and I'm afraid C-g will > have problems when bignums get large. Even if memory isn't exhausted, creating a bignum larger than 16 GB (our most-positive-bignum) results in an immediate crash with external libgmp (Linux, x86_64), and that appears not to be easy to fix without modifying gmp. > I don't have a good handle on this stuff > yet. I have put in some sanity checks (e.g., see check_bignum_size in emacs.c) > but I suspect more are needed. In particular, Fexpt will need to be careful as > it is a good way to explode a bignum's size. That and left shifts are probably the ones to worry about for now. Creating a large bignum by repeated multiplication will require at least some intermediate bignums, which need to be allocated and copied and thus probably alert the user to something going on.