[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

bug#32463: 27.0.50; (logior -1) => 4611686018427387903

From: Paul Eggert
Subject: bug#32463: 27.0.50; (logior -1) => 4611686018427387903
Date: Sun, 19 Aug 2018 03:59:21 -0700
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1

Pip Cet wrote:

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.

Is there a libgmp bug report for this? or is there a reasonable way to characterize this arbitrary limitation in libgmp, so that Emacs does not go over the limit and crash? I've already put in one limit, and we can tighten that limit (or add more checks) if we know what libgmp's limits are.

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.

expt does bignums now too, so that's one more point of failure in this area.

reply via email to

[Prev in Thread] Current Thread [Next in Thread]