GNU bug report logs - #68690
Segmentation fault building with native-comp

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Package: emacs;

Reported by: john muhl <jm <at> pub.pink>

Date: Wed, 24 Jan 2024 16:44:02 UTC

Severity: normal

Done: Stefan Monnier <monnier <at> iro.umontreal.ca>

Bug is archived. No further changes may be made.

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Message #95 received at 68690 <at> debbugs.gnu.org (full text, mbox):

From: Mattias EngdegÄrd <mattias.engdegard <at> gmail.com>
To: Stefan Monnier <monnier <at> iro.umontreal.ca>
Cc: Gerd Möllmann <gerd.moellmann <at> gmail.com>,
 Eli Zaretskii <eliz <at> gnu.org>, jm <at> pub.pink, 68690 <at> debbugs.gnu.org
Subject: Re: bug#68690: Segmentation fault building with native-comp
Date: Fri, 26 Jan 2024 17:07:15 +0100
25 jan. 2024 kl. 23.39 skrev Stefan Monnier <monnier <at> iro.umontreal.ca>:

> AFAIK the current DOHASH code in `master` works fine (tho a bit ugly).

I think it's less good (and more complex) than not trying to cache anything at all where the compiler actually will help out a bit, and it's slower than the fast caching version.

> The build failure didn't come via maphash` but via the DOHASH in
> `comp.c` that calls `compile_function` (which apparently can cause the
> hash table to be resized).

Do you know which one? It's quite possible that that code wasn't written taking into account the problems of extending the table being iterated over. We should definitely ask Andrea.

Meanwhile, I suggest adding a DOHASH_SAFE (simple, safe) to be used in these cases, including Fmaphash, and use the (someone less simple, fast) DOHASH in my previous patch with an extra assertion to catch mistakes elsewhere in checking builds.





This bug report was last modified 1 year and 116 days ago.

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