From mboxrd@z Thu Jan  1 00:00:00 1970
From: Maxim Cournoyer <maxim.cournoyer@gmail.com>
Subject: Re: 02/02: gnu: next: Compress the executable.
Date: Sun, 29 Sep 2019 22:24:09 +0900
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In-Reply-To: <87v9tcm8ws.fsf@gnu.org> ("Ludovic
 \=\?utf-8\?Q\?Court\=C3\=A8s\=22'\?\=
 \=\?utf-8\?Q\?s\?\= message of "Sat, 28 Sep 2019 23:02:27 +0200")
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To: Ludovic =?utf-8?Q?Court=C3=A8s?= <ludo@gnu.org>
Cc: guix-devel@gnu.org

Hi Pierre,

Ludovic Court=C3=A8s <ludo@gnu.org> writes:

> Howdy!
>
> Pierre Neidhardt <mail@ambrevar.xyz> skribis:
>
>> Duh, got it: if next-1.3.1-lib is grafted, then the path to SQLite,
>> libfixposix, etc. _inside the compress binary_ will not be updated.
>> So if we garbage-collect after that, the binary will try to FFI-load
>> non-existing libraries.
>
> Exactly!
>
>> Note that this is only a problem because Next depends on FFI libraries.
>> Compressing pure-SBCL binaries should not be a problem.
>
> It=E2=80=99s a problem in general: any store reference in a compressed fi=
le is
> invisible to the GC and to the grafting code.
>
> Ludo=E2=80=99.

In case you were not thinking about it, Btrfs compression gives you the
best of both worlds -- Guix operates on seemingly uncompressed data,
while in reality everything (not just SBCL binaries) is compressed to
reduce disk space usage and speed up read/writes.

Maxim