Subject: bug#42420: git-fetch origins produce same store output when set recursive is set to true or false

From: Maxim Cournoyer <[email-masked]>
Date: Sun, 29 Nov 2020 23:06:09 -0500

Hello,

Leo Famulari <[email-masked]> writes:

> On Sat, Nov 28, 2020 at 12:23:28AM -0500, Maxim Cournoyer wrote:
>> Is there an action to do here, or should we simply close it?
>
> If we have a good idea for how to improve the situation, we should use
> it. Otherwise, we can close the bug. It's something that confuses a lot
> of people the first time but, once you learn what's happening, it's easy
> to avoid in the future.

I don't; it'd involve changing the way fixed-output derivations are
cached, such as keeping metadata about the sources for fixed hash
derivations (e.g., "There's a hash in the store matching what the
sources tells me, but was it produced from the same origin source?"),
and I don't see how that'd be a good thing.  Note that 'guix build
--source --check' can be used when in doubt that the origin really
computes to the in-store item matching its declared hash.

I've just documented so in the hope users will find it in the manual
when they stumble on such a situation; see commit
3462678bc346c2f6ea81245d6842264b6dccd945.

I'm closing the issue for now.

We can try to do more if it comes back too often.

Thank you,

Maxim