bug#46111: closed (Reverting fns.c hash function due to OpenBSD/SPARC64 compile breaking)

[GNU bug Tracking System]

Your message dated Thu, 28 Jan 2021 12:30:22 -0500
with message-id <jwvzh0tug23.fsf-monnier+emacs@gnu.org>
and subject line Re: bug#46111: Reverting fns.c hash function due to 
OpenBSD/SPARC64 compile breaking
has caused the debbugs.gnu.org bug report #46111,
regarding Reverting fns.c hash function due to OpenBSD/SPARC64 compile breaking
to be marked as done.

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-- 
46111: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=46111
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> --- Begin Message ---
>
>
>
> Subject: 
>
> Reverting fns.c hash function due to OpenBSD/SPARC64 compile breaking
>
>
>
>
> Date: 
>
> Mon, 25 Jan 2021 22:37:53 -0800
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>
>
> User-agent: 
>
> Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (Gojō) APEL-LB/10.8 EasyPG/1.0.0 Emacs/27.1 (sparc64-unknown-openbsd) MULE/6.0 (HANACHIRUSATO)
>
>
>
>
> I'm not an expert on C, OpenBSD, or SPARC64, but I did notice
> emacs-current was not compiling.
>
> During a gmake, bootstrap-emacs would get a SIGBUS and fail. Running
> gdb led me to the hash_string function where it seemed to be failing.
>
> Reverting the hash_string function to a previous version seems to have
> fixed the issue.
>
> If I had to guess, it may have something to do with SPARC64 alignment.
>
> I don't have an updated AMD64 OpenBSD box running at the moment, but if you
> would like me to test there, I could find a way.
>
> I understand that reverting this function might not be the best way
> forward, but wrote a patch just in case that reverts hash_string to an
> earlier version that compiles on OpenBSD/SPARC64.
>
> I am already signed all my GNU contributor docs.
>
> --[[text/plain; type=patch; 
> name="0001-Reverting-hash_string-function-due-to-problem-on-Ope.patch"
> Content-Disposition: attachment; filename="0001-Reverting-hasattach 
> filh_string-function-due-to-problem-on-Ope.patch"][base64]]
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> --- End Message ---
> --- Begin Message ---
>
>
>
> Subject: 
>
> Re: bug#46111: Reverting fns.c hash function due to OpenBSD/SPARC64 compile breaking
>
>
>
>
> Date: 
>
> Thu, 28 Jan 2021 12:30:22 -0500
>
>
>
>
> User-agent: 
>
> Gnus/5.13 (Gnus v5.13) Emacs/28.0.50 (gnu/linux)
>
>
>
>
> > AFAIK, memcpy itself optimizes: once it gets to aligned address, it
> > starts copying words instead of bytes.
>
> I don't know what this `memcpy` code expands to on sparc64, but since it
> turns into a plain `mov` on x86, I simplified the code to always use
> `memcpy`.
>
>
>         Stefan
>
>
>
> --- End Message ---